Space HSC Questions1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 2001 D A A C C B B D B A D D C C D 2002 B A B B D A A C C B A C C B A 2003 B A B A B B D C C A B D D D A 2004 B A D B A B A C A A C B A B B 2005 A D B D C B A C C B B A A B C 2006 C B D B D A D A B A A C D C A 2007 A A B D D D C D C A D A C C A 2008 C C B A C A C B B A D B A D B 2009 C A C D C A C C A B B D B C A 2010 C D A B D B D C C D D B D C B A D C B B 2011 C B B C B C C A B D D A A A C B B B D D 2002 Question 3 9.2.1 2003 9.2.1 2003 9.2.1 2011 9.2.1.2. 1 The table shows the value of the acceleration due to gravity on the surface of Earth and on the surface of Mercury. A person has a weight of 550 N on the surface of Earth. What would be the person’s weight on the surface of Mercury? (A) 56.1 N (B) 213 N (C) 550 N (D) 1420 N Question 1 The weight of an astronaut on the Moon is 1/6 of her weight on Earth. What is the acceleration due to gravity on the Moon? Question 17 (6 marks) A satellite of mass 150 kg is launched from Earth’s surface into a uniform circular orbit of radius 7.5 × 106 m. (a) Calculate the magnitude of the gravitational potential energy Ep of the satellite. (1 mark) Question 23 (7 marks) A rocket launches a satellite into an orbit 350 km above Earth’s surface. The weight of the satellite is 14.0 kN at launch, and is 12.6 kN when in orbit. (Radius of Earth = 6380 km, mass of Earth = 5.97 × 1024 kg) (a) Why does the weight of the satellite change? 2007 9.2.1.2. 3 (1 mark) Question 3 The gravitational potential energy of a given mass is known at both Earth’s surface and at a fixed distance above Earth. What CANNOT be determined by comparing these two values of gravitational potential energy? (A) The mass of Earth (B) The speed of rotation of Earth (C) The escape velocity of a satellite from Earth 2008 9.2.1.2. 3 (D) The work done in moving between the two points Question 17 (5 marks) The graph below represents the gravitational potential energy (Ep) of a mass as it is raised above Earth’s surface. (a)From the graph, what is the gravitational potential energy of the mass when it is one Earth radius above Earth’s surface? (1 mark) (b)Use an equation to explain why the graph is a curve and not a straight line. 2009 9.2.1.2. 3 (1 mark) Question 3 A satellite is moved from a geostationary orbit to a higher orbit. Which statement about the orbit change is correct? (A) During the move the gravitational potential energy decreases. (B) The change in gravitational potential energy is independent of the mass of the satellite. (C) The work done is the difference between the gravitational potential energy of the higher orbit and that of the geostationary orbit. 2006 9.2.1.2. 3 9.2.1.2. 1 (D) The work done is the energy required to move the satellite, which is in the gravitational field, from a very large distance away, to the higher orbit. Question 1 Given that G is the universal gravitational constant, and g is the magnitude of the acceleration due to gravity, which statement is true? (A) The values of G and g depend on location. (B) The values of G and g are independent of location. (C) G is the same everywhere in the universe, but g is not. 2006 9.2.1.2. 3 (D) g is the same everywhere in the universe, but G is not. Question 18 (3 marks) An object is stationary in space and located at a distance 10 000 km from the centre of a certain planet. It is found that 1.0 MJ of work needs to be done to move the object to a stationary point 20 000 km from the centre of the planet. 9.2.1.2. 2 Calculate how much more work needs to be done to move the object to a stationary point 80,000 km from the centre of the planet. 2008 Question 1 An object on Earth has a weight of 490N and experiences an acceleration due to gravity of 9.8m.s–2. On Mars, this object would experience an acceleration due to gravity of 3.7m.s–2. 9.2.1.3. 3 On Mars, what would be the weight of this object? 2010 9.2.1.3. 3 Question 7 The acceleration due to gravity on the surface of Mercury is 3.6 m s−2. How much does a 2.0 kg brick weigh on Earth and on Mercury? 2009 9.2.1.3. 3 9.1.12.4 b 2001 9.2.1.3. 3 9.2.1.2. 1 2001 9.2.1.3. 3 9.2.1.2. 1 Question 16 (3 marks) NASA recently landed a space probe on an asteroid found between the orbits of Earth and Mars. The 500 kg space probe had a weight of 2.5 N when it landed on the asteroid. (a) What would be the weight of this space probe on the surface of Earth? (1 mark) Question 1 A person has a mass of 70.0 kg. What is the weight of the person at the Earth’s surface? (A) 70.0 kg (B) 70.0 N (C) 686 kg (D) 686 N Question 18 (6 marks) A 30 kg object, A, was fired from a cannon in projectile motion. When the projectile was at its maximum height of 25 m, its speed was 20 m s–1. An identical object, B, was attached to a mechanical arm and moved at a constant speed of 20 m s–1 in a vertical half-circle. The length of the arm was 25 m. 9.2.1.1 Ignore air resistance. (a) Calculate the force acting on object A at its maximum height. (1 mark) 2002 9.2.2 Question 4 The diagram shows four positions of a car on a roller coaster ride. 2002 At which point during this ride would the occupant experience maximum ‘g force’? (A) P (B) Q (C) R (D) S Question 1 The diagram shows the trajectory of a golf ball. 9.2.2 Which set of arrows shows the direction of the acceleration of the ball at points P and Q respectively? 2002 Question 5 The table contains information related to two planets orbiting a distant star. 9.2.2 The orbital period of the planet Ba can be determined by using data selected from this table. What is the orbital period of the planet Ba? 2003 9.2.2 (A) 3.10 × 107 s (B) 5.51 × 107 s (C) 1.39 × 108 s (D) 2.47 × 108 s Question 2 A satellite moves in uniform circular motion around Earth. The following table shows the symbols used in the diagrams below. These diagrams are NOT drawn to scale. Which diagram shows the direction of F and v at the position indicated? 2002 9.2.2 Question 21 (4 marks) In his science fiction novel From the Earth to the Moon, Jules Verne describes how to launch a capsule from a cannon to land on the moon. To reach the moon, the capsule must leave the cannon with a speed of 1.06 × 104 m.s−1. The cannon has a length of 215 m, over which the capsule can be assumed to accelerate constantly. (a) Calculate the magnitude of the acceleration required to achieve this speed using this cannon. (2 marks) (b) Referring to your answer in part (a), explain why Jules Verne’s method is unsuitable for sending a living person to the moon. (2 marks) 2003 Question 4 9.2.2 2003 9.2.2 Two planets, X and Y, travel around a star in the same direction, in circular orbits. Planet X completes one revolution about the star in time T. The radii of the orbits are in the ratio 1:4. How many revolutions does planet Y make about the star in the same time T? (A) 1/8 revolution (B) 1/2 revolution (C) 2 revolutions (D) 8 revolutions Question 16 (6 marks) A student performed a first-hand investigation to examine projectile motion. A ball resting on a horizontal table was given an initial push at X, resulting in the ball following the path XYZ as shown. A data logger used the motion sensor to measure the horizontal distance to the ball. When the ball was at position Y, a distance of 1.50 m from the motion sensor, it left the edge of the table. In the first trial, the range was 0.60 m. The graph below was obtained from the data logger. (a) For this trial, determine the horizontal speed of the ball as it left the edge of the table. (1 mark) (b) The experiment was repeated with the ball leaving the table at different speeds. Graph the relationship between the range and the horizontal speed at Y. Identify on your graph the results from the first trial. (3 marks) (c) The apparatus described in this first-hand investigation was used to carry out an identical experiment on another planet where the acceleration due to gravity is less than that on Earth. The horizontal speed of the ball as it left the table on the planet was the same as in part (a). Compare the range of the ball on the planet to that on Earth. Explain your answer. (2 marks) 2003 Question 17 (6 marks) 9.2.2 A satellite of mass 150 kg is launched from Earth’s surface into a uniform circular orbit of radius 7.5 × 106 m. (a) Calculate the magnitude of the gravitational potential energy Ep of the satellite. (1 mark) (b) From this uniform circular orbit, the satellite can escape Earth’s gravitational field when its kinetic energy is equal to the magnitude of the gravitational potential energy. Use this relationship to calculate the escape velocity of the satellite. (3 marks) (c) Discuss the effect of Earth’s rotational motion on the launch of this satellite. 2010 9.2.2.1 (2 marks) Question 4 A ball was thrown upward at an angle of 45°. It landed at the same height as thrown. Which graph best represents the kinetic energy of the ball during its time of flight? 8.4.3.2. 1 2001 9.2.2.2. 1 Question 15 A student releases a ball from eye level. The ball bounces several times. Which velocity vs. time graph best represents the ball’s motion? 2004 Question 1 The picture shows a game of cricket. 9.2.2.2. 1 The picture shows two consecutive shots by the batsman. Both balls reach the same maximum height above the ground but ball Q travels twice as far as ball P. Which of the following is DIFFERENT for balls P and Q? 2005 (A) Time of flight (B) Initial velocity (C) Gravitational force (D) Gravitational acceleration Question 1 A ball thrown in the air traces a path as shown below. 9.2.2.2. 1 Which of the following statements is true? 2005 9.2.2.2. 1 2006 9.2.2.2. 1 (A) The velocity of the ball keeps changing. (B) The acceleration of the ball keeps changing. (C) The velocity of the ball at the top of its motion is zero. (D) The acceleration of the ball at the top of its motion is zero. Question 5 Napoleon attacked Moscow in 1812 with his cannon firing a shot at an elevation angle of 40°. Napoleon then decided to fire a second shot at the same speed but at an elevation angle of 50°. Which of the following observations would Napoleon expect to be true about the second shot when compared with the first? (A) Longer range (B) Shorter range (C) Longer time of flight (D) Shorter time of flight Question 4 A stone is thrown horizontally from the top of a cliff and falls onto the beach below. Which acceleration–time graph best describes the motion of the stone? 2009 9.2.2.2. 1 Question 4 A device launches two identical balls (x and y) simultaneously in a horizontal direction from the same height. The results are shown. Which statement correctly describes what happens? 2010 9.2.2.2. 2 2005 9.2.2.2. 3 (A) x hits the ground before y as it is closer to the launch site. (B) y hits the ground before x as it has a higher launch velocity. (C) x and y hit the ground simultaneously with the same velocity. (D) x and y hit the ground simultaneously with different velocities. Question 2 Which of the following best describes Galileo’s analysis of projectile motion? (A) A projectile launched with a great enough velocity would escape Earth’s gravity. (B) A projectile would travel in a straight line until it ran out of momentum, then it would fall. (C) A projectile launched from the equator towards the east with a great enough velocity would orbit Earth. (D) A projectile would travel in a parabolic path because it has constant horizontal velocity and constant vertical acceleration. Question 3 The initial velocity required by a space probe to just escape the gravitational pull of a planet is called escape velocity. Which of the following quantities does NOT affect the magnitude of the escape velocity? 2007 9.2.2.2. 6 2008 9.2.2.2. 7 2010 9.2.2.2. 7 (A) Mass of the planet (B) Mass of the space probe (C) Radius of the planet (D) Universal gravitational constant Question 17 (4 marks) The diagram shows the position X on Earth’s surface from which a satellite is to be launched into a geostationary orbit. (a) On the diagram, draw an arrow to show the direction of launch from X, and justify your choice. (1 mark) Question 19 (8 marks) (a) Explain the changes in momentum when a satellite fires its propulsion system. (3 marks) Question 25 (4 marks) The mass of a rocket decreases during launch as it burns fuel, as shown in the graph. The rocket engine produces a constant upward force on the rocket. 9.2.2.2. 7 9.2.2.2. 5 (a) How does the law of conservation of momentum apply to the motion of the rocket? (2 marks) (b) Why do the g-forces on an astronaut in the rocket differ at times t1 and t2? (2 marks) 2011 9.2.2.2. 7 Question 8 A rocket is launched. Its engine produces a constant thrust for the first 10 seconds and is then switched off. Which graph best illustrates the g-force experienced by an astronaut in the rocket? 9.2.2.2. 5 2001 9.2.2.2. 8 Question 13 A rocket car moves on a straight horizontal track. Half of the initial mass of the rocket car is propellant. During the run, propellant is consumed at a constant rate and ejected at a constant nozzle velocity. Which of the following best describes the force propelling the rocket car, and the magnitude of the acceleration of the rocket car while the propellant is being ejected? 2001 9.2.2.2. 8 Question 17 (6 marks) A rocket was launched vertically to probe the upper atmosphere. The vertical velocity of the rocket as a function of time is shown in the graph. 8.4.2.2. 6 (a) Using either words or calculations, compare the acceleration of the rocket at t = 20 s with its acceleration at t = 100 s. (2 marks) (b) Account for the shape of the graph over the range of time shown. 2004 (4 marks) Question 18 (4 marks) A car with a mass of 800 kg travels at a constant speed of 7.5 m.s−1 on a roundabout so that it 9.2.2.2. 8 follows a circular path with a radius of 16 m. A person observing this situation makes the following statement. ‘There is no net force acting on the car because the speed is constant and the friction between the tyres and the road balances the centripetal force acting on the car.’ 2006 9.2.2.2. 8 2008 9.2.2.2. 8 2001 9.2.2.2. 8 Assess this statement. Support your answer with an analysis of the horizontal forces acting on the car, using the numerical data provided above. Question 2 A mass attached to a length of string is moving in a circular path around a central point, O, on a flat, horizontal, frictionless table. This is depicted in the diagram below. The string breaks as the mass passes point X. Which line best depicts the subsequent path of the mass? (A) Line A (B) Line B (C) Line C (D) Line D Question 2 Which of these statements best describes the forces acting on a satellite in orbit around Earth? (A) Although gravity has no effect, there is still an outward force. (B) The satellite is kept up by an outward force that balances the force due to gravity. (C) Gravity is the only force acting on the satellite and this results in an inwardacceleration. (D) The effect of gravity is negligible, the satellite is kept in orbit by its momentum andthe net force on it is zero. Question 5 The graph shows the forces experienced by an astronaut during a rocket launch into a stable orbit. 9.2.2.2. 5 2006 9.2.2.2. 9 In which time interval was the acceleration of the rocket the greatest? (A) S–T (B) T–U (C) U– V (D) V–W Question 17 (6 marks) Parts of a space mission involve a spacecraft spending time in geostationary orbit, and then returning safely to Earth. Analyse the forces acting on this spacecraft during these parts of the mission. 9.2.2.2. 8 8.4.2.2. 10 2010 9.2.2.2. 10 2005 9.2.2.2. Question 1 The International Space Station orbits Earth at an altitude of approximately 330 km. Another satellite, Meteosat, is in geostationary orbit at an altitude of 36 000 km. Which of the following correctly compares the orbital velocity and orbital period of these satellites? Question 4 A space probe, P, is in a stable orbit around a small, distant planet. The 10 probe fires a forward-facing rocket that reduces its orbital speed by half. Which of the following best illustrates the subsequent motion of the probe? 2011 Question 16 A satellite is orbiting a planet at a constant speed. Which of the following statements is correct? 9.2.2.2. 10 2004 9.2.2.2. 10 (A) The satellite is not accelerating. (B) The orbit of the satellite has a fixed radius. (C) Fuel must be used to supply a constant thrust to the satellite. (D) The centripetal force on the satellite is balanced by the gravitational force. Question 19 (6 marks) On 11 June 2003 the Mars Rover called Spirit was launched on a satellite from Earth when the planets were in the positions shown in the diagram below. The satellite arrived at Mars on 3 December 2003. (a) Indicate on the diagram the approximate positions of Earth and Mars on 3 December 2003 and show the satellite’s trajectory to Mars. (3 marks) (b) Discuss the effect of Earth’s motion on the launch and trajectory to Mars 9.2.2.2. 6 of this satellite (3 marks) 2005 9.2.2.2. 11 2011 9.2.2.2. 11 2010 Question 2 Why would a satellite in low orbit around Earth eventually fall to Earth? (A) It is not in a geostationary orbit. (B) Gravity is too strong at low orbits. (C) The sun’s solar wind pushes it out of orbit. (D) The upper atmosphere gradually slows it down. Question 1 What is the main cause of orbital decay of a satellite in low Earth orbit? (A) Tidal effects of the Moon (B) The Sun’s gravitational field (C) Friction between the atmosphere and the satellite (D) The interaction of the solar wind with the satellite Question 21 (2 marks) The optimum angle for safe reentry of a space vehicle into Earth’s atmosphere is angle B. 9.2.2.2. 13 9.2.2.2. 12 Outline consequences of the space vehicle entering the atmosphere at angle A AND angle C. 2004 9.2.2.3. 1 2007 9.2.2.3. 1 Question 16 (4 marks) A projectile is fired at a velocity of 50 m.s–1 at an angle of 30° to the horizontal. Determine the range of the projectile. Question 5 A cannon ball is fired vertically upward from a stationary boat. Which pair of graphs best describes the velocity, v, and acceleration, a, of the cannon ball as functions of time, t? Ignore air resistance. 2008 9.2.2.3. 1 2008 9.2.2.3. 1 Question 3 An aeroplane is flying horizontally over level ground. It has an altitude of 490m and a velocity of 100ms–1. As the aeroplane passes directly above a cross marked on the ground, an object is released from the aeroplane. How far away from the cross will this object land? (A) 490m (B) 1000m (C) 10000m (D) 49000m Question 4 An investigation was performed to determine the acceleration due to gravity. A ball was dropped from various heights and the time it took to reach the ground from each height was measured. The results were graphed with the independent variable on the horizontal axis. Which graph best represents the relationship between the variables? 2010 9.2.2.3. 1 Question 22 (5 marks) An astronaut on the Moon throws a stone from the top of a cliff. The stone hits the ground below 21.0 seconds later. The acceleration due to gravity on the moon is 1.6 ms–2. 9.2.2.3. 1 9.2.2.3. 1 (a) Calculate the horizontal component of the stone’s initial velocity. Show your working. (1 mark) (b) Calculate the vertical component of the stone’s initial velocity. Show your working. (2 marks) 2011 9.2.2.3. (c) On the diagram, sketch the path that the stone would follow if the acceleration due to gravity was higher. The initial velocity is the same. (2 marks) Question 15 A marble rolls off a 1.0 m high horizontal table with an initial velocity of 4.0 m s–1. 1 2004 9.2.2.3. 1 9.1 2001 9.2.2.3. 2 2006 How long will it take the marble to hit the floor? (A) 0.20 s (B) 0.25 s (C) 0.45 s (D) 3.20 s Question 27 (4 marks) A sports magazine commenting on the athletic ability of Michael Jordan, the famous basketball player said: ‘Being an athlete takes more brains than brawn. It takes time and effort. It takes endurance and commitment. It takes an athlete who can stay in the air for 2.5 seconds while shooting a goal; an athlete who knows which laws of physics keep him there.’ Assess the information presented in this magazine, using appropriate calculations to support your argument. Question 7 An astronaut is standing on Mars. The astronaut throws an object of mass 0.30 kg vertically upward at an initial speed of 9.0 m s–1. It reaches a maximum height of 11 metres. What is the magnitude of the acceleration of the object? (A) 1.4 m s–2 (B) 3.7 m s–2 (C) 9.0 m s–2 (D) 9.8 m s–2 Question 16 (6 marks) A projectile leaves the ground at point A with velocity components as shown in the diagram. It follows the path given by the dotted line and lands at point B. (a) State the horizontal component of the projectile’s velocity when it lands. (1 mark) (b) Find the magnitude of the initial velocity of the projectile. (1 mark) 9.2.2.3. 1 9.2.2.3. 2 9.2.2.3. 2 9.2.2.3. (c) Calculate the maximum height attained by the projectile. (2 marks) 2 (d) Calculate the range of the projectile, if it lands level with its starting position. 2007 Question 16 (5 marks) A group of students conducted an investigation in which ball bearings were released from various points on a ramp. The ball bearings rolled down the ramp to the edge of a table at point P as shown. Their ranges were measured. 9.2.2.3. 2 (2 marks) 9.2.2.3. 1 9.2.2.2. 1 The results are shown in the table. (a) Plot the data from the table and draw a curve of best fit. (2 marks) (b)(i) Using your graph, predict the range of a ball bearing released from a height of 80cm above point P. (1 mark) (ii) Calculate the horizontal velocity of the ball bearing released from a height of 80 cm above point P. (2 marks) 2009 9.2.2.3. 2 Question 19 (6 marks) An electron is emitted from a mineral sample, and travels through aperture A into a spectrometer at an angle of 60° with a speed of 6.0 × 106ms-1. 9.2.2.3. 1 9.1.14.3 b 9.1.14.1 f 9.1.13.1 d 9.1.12.4 b 2001 9.2.2.3. 2 (b) The electron experiences constant acceleration and eventually strikes the detector, D. What is the time taken for the electron to travel from A to D? (3 marks) Question 18 (6 marks) A 30 kg object, A, was fired from a cannon in projectile motion. When the projectile was at its maximum height of 25 m, its speed was 20 m s–1. An identical object, B, was attached to a mechanical arm and moved at a constant speed of 20 m s–1 in a vertical half-circle. The length of the arm was 25 m. 9.2.2.3. 3 9.2.2.3. 2 9.2.2.3. 1 9.2.2.2. 9 9.2.2.2. 2 9.2.2.2. Ignore air resistance. (b) Calculate the time it would take object A to reach the ground from its position of maximum height. (2 marks) (c) Describe and compare the vertical forces acting on objects A and B at their maximum heights. (3 marks) 1 2010 9.2.2.3. 4 Question 5 A 200 g mass is swung in a horizontal circle as shown. It completes 5 revolutions in 3 seconds. The circle has a 2 m diameter. 9.2.2.2. 8 2009 9.2.2.3. 4 9.1.14.1 f 9.1.12.4 b 2005 9.2.2.3. 5 9.2.2.2. 10 Which of the following forces is closest to that required to keep the mass moving in this circle? (A) 0.50 N (B) 2.5 N (C) 10 N (D) 20 N Question 2 A satellite is moving in a circular orbit of radius 7.0 × 106 m around Earth. If the speed of the satellite is 8.1 × 103 ms–1, what is its centripetal acceleration? (A) 9.4 m s–2 (B) 9.8 m s–2 (C) 5.6 × 1025 ms–2 (D) 3.9 × 1032 ms–2 Question 16 (5 marks) From nearest to furthest, the four satellite moons of Jupiter first observed by Galileo in the year 1610 are called Io, Europa, Ganymede and Callisto. For the first three moons, the orbital period T of each is exactly twice the period of the one orbiting immediately inside it. That is, TEuropa = 2 × TIo TGanymede = 2 × TEuropa The mass of Jupiter is 1.90 × 1027 kg, and the orbital radius of Io is 421 600 km. 2006 9.2.2.3. 5 (a) Use Kepler’s Law of Periods to calculate Ganymede’s orbital radius. (2 marks) (b) Calculate Ganymede’s orbital speed. (3 marks) Question 5 Two satellites, X and Y, are in circular orbits around Earth. Their masses are identical and their orbital radii are R and 16R, respectively. What is the ratio of their orbital periods, TX:TY? (A) 1:4 9.2.2.2. 10 2010 9.2.2.3. 5 (B) 1:16 (C) 1:32 (D) 1:64 Question 24 (3 marks) In 2014 the James Webb Space Telescope (JWST) will be placed in orbit around the Sun. Earth and the JWST will follow the orbits shown, with identical orbital periods. This appears to contradict Kepler’s law of periods. 9.2.2.2. 10 9.2.2.2. 8 Why is it possible for the JWST to orbit the Sun with the same orbital period as Earth? In your answer, refer to Kepler’s law of periods. 2011 9.2.2.3. 4 9.2.2.3. 5 9.2.2.2. 10 2007 9.2.2.3. 5 9.2.2.2. 9 Question 23 (7 marks) A rocket launches a satellite into an orbit 350 km above Earth’s surface. The weight of the satellite is 14.0 kN at launch, and is 12.6 kN when in orbit. (Radius of Earth = 6380 km, mass of Earth = 5.97 × 1024 kg) (b) Calculate the orbital velocity of this satellite. (2 marks) (c) Explain TWO effects that a reduction in altitude would have on the motion of this satellite. (4 marks) Question 17 (4 marks) A satellite is to be launched into a geostationary orbit. (b) Given that the radius of Earth is 6.38 × 106 m, calculate the height of the satellite above Earth’s surface. (3 marks) 2008 Question 19 (8 marks) (b) A satellite is propelled from Orbit 1 to Orbit 2 as shown in the diagram. 9.2.2.3. 5 9.2.2.3. 4 Orbit 2 has a radius of 27,000km. What is the satellite’s speed in this orbit? (3 marks) (c) The radius of Orbit 2 is four times that of Orbit 1. What is the ratio of the new orbital period to the original period? (2 marks) 2002 9.2.3 2002 9.2.3 Question 17* (4 marks) Describe TWO difficulties associated with effective or reliable communications between satellites and Earth. Question 18* (3 marks) The graph shows the percentage transmission of electromagnetic radiation of various wavelengths through the Earth’s atmosphere. The Voyager II spacecraft transmits electromagnetic radiation to Earth at a frequency of 2295 MHz. Use the graph to justify the use of this transmission frequency. 2003 9.2.3 9.2.2 Question 3 For a satellite moving in uniform circular motion around Earth, the centripetal force is provided by the gravitational force. The mass of Earth is ME. The mass of the satellite is MS. The distance of the satellite from the centre of Earth is d. Which of the following equations should be used to calculate the speed of this satellite? 2009 9.2.3.2. 1 2009 Question 1 A fast-moving space probe passes close to a planet. During its journey, how does the gravitational field of the planet affect the speed and direction of the probe? Question 5 During a lunar eclipse, Earth moves between the Sun and the Moon. 9.2.3.2. 3 What happens to the force exerted by the Sun on the Moon? (A) It increases. (B) It decreases. (C) It remains unchanged. 2005 9.2.3.2. 3 9.2.3.2. 2 2001 9.2.3.3. 1 9.2.3.2. 2 2007 9.2.3.3. 2 2011 9.2.3.3. 2 9.2.1.2. 3 2011 9.2.3.3. 2 9.2.1.2. 3 2004 9.2.2.3. 5 (D) It depends on the closeness of Earth to the Moon. Question 19 (4 marks) In 1970 NASA launched Apollo 13, their third mission planned to land humans on the Moon. Half-way to the Moon a huge explosion crippled the spacecraft. The only way home for the astronauts was to fly around the back of the Moon and then fire the rocket engine to take the craft out of lunar orbit and put it into an Earth-bound trajectory. At the completion of the rocket engine burn, mission leader Jim Lovell was heard to say, ‘We just put Isaac Newton in the driver’s seat’. Given that the spacecraft returned safely to Earth, justify Jim Lovell’s statement. Question 9* Which is the most suitable means of reliable and continuous communication between an orbiting satellite and Earth? (A) Light from a green laser (B) Microwaves (C) Radio waves (D) Sound waves Question 4 The acceleration due to gravity on Earth’s surface is g. Suppose the radius of Earth was reduced to a quarter of its present value while its mass remained the same. What would be the new value of the acceleration due to gravity on the surface? (A) 1/16 g (B) 1/4 g (C) 4 g (D) 16 g Question 2 A 60 kg object has a weight of 240 N on the surface of Planet X. What is the acceleration due to gravity on the surface of Planet X? (A) 0.25 m s–2 (B) 4 m s–2 (C) 250 m s–2 (D) 14 400 m s–2 Question 20 A satellite, initially in a low Earth orbit, is moved to a new orbit where its gravitational potential energy is half its initial value. What is the gravitational force experienced by the satellite in its new orbit? (A) Half the initial force (B) Twice the initial force (C) Four times the initial force (D) One quarter the initial force Question 17 (6 marks) In July 1969 the Apollo 11 Command Module with Michael Collins on board orbited the Moon waiting for the Ascent Module to return from the Moon’s surface. The mass of the Command Module was 9.98 × 103 kg, its period was 119 minutes, and the radius of its orbit from the Moon’s centre was 1.85 × 106 metres. (a) Assuming the Command Module was in circular orbit, calculate (i) the mass of the Moon; (2 marks) 9.2.3.3. 2 9.2.2.3. 5 (ii) the magnitude of the orbital velocity of the Command Module. (2 marks) 9.2.2.3. 4 (b) The docking of the Ascent Module with the Command Module resulted in an increase in mass of the orbiting spacecraft. The spacecraft remained at the same altitude. This docking procedure made no difference to the orbital speed. Justify this statement. (2 marks) 9.2.2.2. 10 2004 Question 2 The diagram shows two planets X and Y of mass m and 4m respectively. 9.2.3.3. 2 9.2.3.2. 2 9.2.1.3. 3 2004 9.2.3.3. 2 9.2.3.2. 3 At the distance d from the centre of planet Y the acceleration due to gravity is 4.0 m s−2. What is the acceleration due to gravity at distance d from the centre of planet X? (A) 1.0 m s−2 (B) 2.0 m s−2 (C) 2.8 m s−2 (D) 4.0 m s−2 Question 3 A spaceship at a distance r metres from the centre of a star experiences a gravitational force of x newtons. The spaceship moves a distance r/2 towards the star. What is the gravitational force acting on the spaceship when it is at this new location? (A) x/2 newtons (B) x newtons (C) 2x newtons 2007 (D) 4x newtons Question 1 A satellite is in orbit around Earth with tangential velocity v as shown. 9.2.3.3. 4 9.2.2.2. 8 2009 9.2.4.3. 2 Which of the following describes the direction of the centripetal force acting on the satellite? (A) Same direction as the gravitational force (B) Opposite direction to the gravitational force (C) Same direction as the tangential velocity (D) Opposite direction to the tangential velocity Question 16 (5 marks) (a) Using labelled diagrams, show how a first-hand investigation could be performed to distinguish between an inertial and a non-inertial frame of reference. (2 marks) 9.2.4.2. 5 9.2.4.2. 4 9.1.12.4 b 2002 9.2.4 2002 9.2.4 (b) Explain how inertial and non-inertial frames of reference relate to the principle of relativity. (3 marks) Question 2 A spaceship is travelling at a very high speed. What effects would be noted by a stationary observer? (A) Time runs slower on the spaceship and it contracts in length. (B) Time runs faster on the spaceship and it contracts in length. (C) Time runs slower on the spaceship and it increases in length. (D) Time runs faster on the spaceship and it increases in length. Question 20 (3 marks) A student is investigating inertial and non-inertial frames of reference. The student carries out a series of activities on a boat floating on a large, calm lake. The boat remained level during these activities. Each activity and the student’s observed results are recorded in the table. Justify the student’s conclusion that: ‘The boat can be regarded as an inertial frame of reference’. 2002 9.2.4 Question 19 (4 marks) In one of Einstein’s famous thought experiments, a passenger travels on a train that passes through a station at 60% of the speed of light. According to the passenger, the length of the train carriage is 22 m from front to rear. (a) A light in the train carriage is switched on. Compare the velocity of the light beam as seen by the passenger on the train and a rail worker standing on the station platform. (1 mark) (b) Calculate the length of the carriage as observed by the rail worker on the station platform. (3 marks) 2003 9.2.4 2003 9.2.4 Question 5 An astronaut set out in a spaceship from Earth orbit to travel to a distant star in our galaxy. The spaceship travelled at a speed of 0.8 c. When the spaceship reached the star the on-board clock showed the astronaut that the journey took 10 years. An identical clock remained on Earth. What time in years had elapsed on this clock when seen from the astronaut’s spaceship? (A) 3.6 (B) 6.0 (C) 10.0 (D) 16.7 Question 18 (6 marks) Michelson and Morley set up an experiment to measure the velocity of Earth relative to the aether. (a) Outline TWO features of the aether model for the transmission of light. (2 marks) (b) Recount the Michelson and Morley experiment, which attempted to measure the relative velocity of Earth through the aether, and describe the results they anticipated. (4 marks) 2005 Question 18 (4 marks) 9.2.4 The idea of a universal aether was first proposed to explain the transmission of light through space. Michelson and Morley attempted to measure the speed of Earth through the aether. Evaluate the impact of the result of the Michelson and Morley experiment on scientific thinking. 2001 Question 19 (4 marks) How does Einstein’s Theory of Special Relativity explain the result of the Michelson–Morley experiment? 9.2.4.2. 11 9.2.4.2. 7 9.2.4.2. 6 9.2.4.2. 5 9.2.4.2. 3 9.2.4.2. 2 2010 9.2.4.2. 3 2011 9.2.4.2. 3 9.2.4.2. 2 Question 6 Which statement about the Michelson-Morley experiment is correct? (A) It was a valid experiment because it tested the principle of relativity. (B) It was a valid experiment because it took into account the known properties of light. (C) It was an invalid experiment because it did not take into account the particle nature of light. (D) It was an invalid experiment because the speed of Earth through the aether was not taken into account. Question 22 (5 marks) (a) What was the purpose of the experiment that Michelson and Morley conducted in 1887? (1 mark) (b) Draw a labelled diagram that outlines how the experiment was performed. (4 marks) 2004 9.2.4.2. 4 Question 6 A ball is dropped by a person sitting on a vehicle that is accelerating uniformly to the right, as shown by the arrow. Which of the following represents the path of the ball, shown at equal time intervals, observed from the frame of reference of the vehicle? 2007 9.2.4.2. 7 2004 9.2.4.2. 9 Question 18 (7 marks) (a)How has our understanding of time been influenced by the discovery of the constancy of the speed of light? (2 marks) Question 5 Two spaceships are both travelling at relativistic speeds. Spaceship Beta shines a light beam forward as shown. What is the speed of the light beam according to an observer on spaceship Alpha? (A) The speed of the light beam is equal to c. (B) The speed of the light beam is less than c. (C) The speed of the light beam is greater than c. 2007 9.2.4.2. 9 2011 9.2.4.2. 9 (D) More information is required about the relative speed of the spaceships. Question 2 A spaceship sitting on its launch pad is measured to have a length L. This spaceship passes an outer planet at a speed of 0.95c. Which observations of the length of the spaceship are correct? Question 9 The diagram shows a stationary spacecraft next to a building, as seen by an observer across the street. A short time later the spacecraft is observed to be travelling vertically upwards at 0.8c, relative to the building. Which diagram best represents the appearance of the moving spacecraft, as seen by the observer? 2011 9.2.4.2. 9 Question 24 (4 marks) Consider the following ‘thought experiment’. A scientist on board a spaceship wishes to synchronise two clocks. To achieve this, beams of light from a source placed midway between the clocks activate photocells, turning on both clocks. The scientist observes the synchronisation of the clocks as the rocket flies past Earth at 0.95c. A person on Earth observes that the clocks are not synchronised. Account for these observations. 2006 9.2.4.3. 1 9.2.4.2. 3 2009 9.2.4.3. 2 9.1.14.1 f 9.1.13.1 a 9.1.11.3 a 9.2.4.2. 5 9.2.4.2. 4 2010 9.2.4.3. 2 9.2.4.2. 4 9.2.4.2. 5 Question 3 What is the main reason why the Michelson-Morley experiment is considered important? (A) It shows the existence of the aether. (B) It suggests that light is an electromagnetic wave. (C) It indicates that light can exhibit interference effects. (D) It provides experimental support for the theory of relativity. Question 17 (5 marks) (a) Using labelled diagrams, show how a first-hand investigation could be performed to distinguish between an inertial and a non-inertial frame of reference. (2 marks) (b) Explain how inertial and non-inertial frames of reference relate to the principle of relativity. (3 marks) Question 23 (5 marks) A train is travelling on a straight horizontal track. A student on the train attaches a mass on a string to the ceiling of the train. The student observes that the mass remains stationary in the position shown. (a) Why does the mass hang with the string at an angle to the vertical? (2 marks) (b) The string then breaks and the mass falls. Indicate the path of the mass on the diagram above. Explain why the mass has taken this path. (3 marks) 2005 9.2.4.3. 4 9.2.4.2. 10 Question 17 (6 marks) Einstein’s 1905 theory of special relativity made several predictions that could not be verified for many years. (a) State ONE such prediction. (1 mark) (b) Describe an experiment to test this prediction. (2 marks) (c) Explain how technological advances since 1905 have made it possible to carry out this experiment. (3 marks) 2007 9.2.4.3. 4 Question 19 (6 marks) This flowchart represents one model of scientific method used to show the relationship between theory and the evidence supporting it. Analyse Einstein’s Theory of Special Relativity and the evidence supporting it as an application of this model of scientific method. 2007 9.2.4.3. 5 2004 9.2.4.3. 5 2001 9.2.4.3. 5 9.2.4.2. 11 Question 18 (7 marks) (b) A piece of radioactive material of mass 2.5 kilogram undergoes radioactivedecay. How much energy is released if 10 grams of this mass are converted to energy during the decay process? (2 marks) Question 4 An object of rest mass 8.0 kg moves at a speed of 0.6c relative to an observer. What is the observed mass of the object? (A) 6.4 kg (B) 10.0 kg (C) 12.5 kg (D) 13.4 kg Question 16 (4 marks) Muons are very short-lived particles that are created when energetic protons collide with each other. A beam of muons can be produced by very-highenergy particle accelerators. The high-speed muons produced for an experiment by the Fermilab accelerator are measured to have a lifetime of 5.0 microseconds. When these muons are brought to rest, their lifetime is measured to be 2.2 microseconds. (a) Name the effect demonstrated by these observations of the lifetimes of the muons. (1 mark) (b) Calculate the velocity of the muons as they leave the accelerator. (3 marks) 2006 Question 25 (6 marks) A simplified cathode ray oscilloscope is depicted below. 9.2.4.3. 5 (b) In a special investigation, the voltage between the cathode and the anode is increased so that an electron gains a velocity of 0.60 c, where c is the speed of light. The electron starts from rest at the cathode. Calculate the mass of this electron in the laboratory frame of reference. (2 marks) (c) The distance between the anode and the screen, as measured in the electron’s frame of reference, is 0.24 m. Calculate this distance as measured in the laboratory frame of reference. (2 marks) 2007 9.2.4.3. 5 2008 9.2.4.3. 5 2009 9.2.4.3. 5 9.1.14.1 f 9.1.13.1 d 9.1.12.4 b 2010 9.2.4.3. 5 9.2.4.2. 5 9.2.4.2. Question 18 (7 marks) (c) A mass is moving in an inertial frame of reference at a velocity v relative to a stationary observer. The observer measures an apparent mass increase of 0.37%. Calculate the value of v in m.s–1. (3 marks) Question 5 A spaceship is travelling away from Earth at 1.8 × 108 ms–1. The time interval between consecutive ticks of a clock on board the spaceship is 0.50s. Each time the clock ticks, a radio pulse is transmitted back to Earth. What is the time interval between consecutive radio pulses as measured on Earth? (A) 0.40s (B) 0.50s (C) 0.63s (D) 0.78s Question 18 (4 marks) The nearest galaxy to ours is the Large Magellanic Cloud, with its centre located 1.70 × 105 light years from Earth. Assume you are in a spacecraft travelling at a speed of 0.99999c toward the Large Magellanic Cloud. (a) In your frame of reference, what is the distance between Earth and the Large Magellanic Cloud? (2 marks) (b) In your frame of reference, how long will it take you to travel from Earth to the Large Magellanic Cloud? (2 marks) Question 3 A scientist at a particle accelerator laboratory observes the lifetime of a particular subatomic particle to be 1.0 × 10−6 s when it is travelling at 0.9999 c. What would the lifetime of the particle be if it were stationary in the laboratory? (A) 1.4 × 10−8 s (B) 4.5 × 10−8 s (C) 1.0 × 10−6 s (D) 7.1 × 10−5 s 4