AQA A-LEVEL PHYSICS PAPER 1 EXAM | QUESTIONS AND
ANSWERS | VERIFIED ANSWERS PLUS RATIONALES | EXAM
ALREADY GRADED A+ | LATEST EXAM
1. Which of the following is a vector quantity?
A) Mass
B) Speed
C) Displacement
D) Temperature
Answer: C – Displacement has both magnitude and direction, unlike scalars.
2. Newton’s law of gravitation states that the gravitational force between two masses is:
A) Directly proportional to distance squared
B) Inversely proportional to distance squared
C) Directly proportional to distance
D) Independent of distance
Answer: B – F=Gm1m2r2F = \frac{G m_1 m_2}{r^2}F=r2Gm1m2, force decreases with the
square of distance.
3. The gravitational field strength ggg at the surface of a planet depends on:
A) Planet’s mass and radius
B) Planet’s density only
C) Satellite’s mass
D) Satellite’s orbital speed
Answer: A – g=GMR2g = \frac{GM}{R^2}g=R2GM, where MMM is mass and RRR is radius.
4. What is the escape velocity from a planet of mass MMM and radius RRR?
A) GMR\sqrt{\frac{GM}{R}}RGM
B) 2GMR\sqrt{\frac{2GM}{R}}R2GM
C) GM2R\frac{GM}{2R}2RGM
D) 2GM2GM2GM
Answer: B – Escape velocity ve=2GMRv_e = \sqrt{\frac{2GM}{R}}ve=R2GM.
5. A satellite moves in a circular orbit at constant speed. Its acceleration is:
A) Zero
B) Toward the center of the orbit
C) Tangential to the orbit
D) Opposite the velocity
Answer: B – Centripetal acceleration always points toward the center of the orbit.
6. The period of a satellite in orbit depends mainly on:
A) Its mass
B) Mass of the central body
,C) Shape of the satellite
D) Its velocity only
Answer: B – Using T2∝r3/GMT^2 \propto r^3/GMT2∝r3/GM, the period depends on the central
mass.
7. The force keeping a planet in orbit around the Sun is:
A) Magnetic force
B) Gravitational force
C) Centripetal force only
D) Nuclear force
Answer: B – Gravity acts as the centripetal force keeping the planet in orbit.
8. Which of these quantities remains constant for a planet in circular orbit?
A) Orbital speed
B) Orbital radius
C) Kinetic energy
D) All of the above
Answer: D – In a circular orbit, speed, radius, and kinetic energy are constant.
9. Kepler’s third law states:
A) T2∝r3T^2 \propto r^3T2∝r3
B) T∝r2T \propto r^2T∝r2
C) r2∝T3r^2 \propto T^3r2∝T3
D) T3∝r2T^3 \propto r^2T3∝r2
Answer: A – The square of orbital period is proportional to the cube of orbital radius.
10. A geostationary satellite has a period of:
A) 12 hours
B) 24 hours
C) 7 days
D) 1 hour
Answer: B – Geostationary satellites orbit once per 24 hours, matching Earth’s rotation.
11. The gravitational potential energy of a satellite near Earth is:
A) 12mv2\frac{1}{2}mv^221mv2
B) mghmghmgh
C) −GMmr-\frac{GMm}{r}−rGMm
D) FdFdFd
Answer: C – Gravitational potential energy in orbit is U=−GMmrU = -
\frac{GMm}{r}U=−rGMm.
12. The kinetic energy of a satellite in a circular orbit is:
A) Equal to its potential energy
B) Half the magnitude of potential energy
C) Double the potential energy
,D) Zero
Answer: B – KE=−12UKE = -\frac{1}{2} UKE=−21U in circular orbit.
13. A satellite is in a higher orbit. Compared to a lower orbit, its orbital speed is:
A) Greater
B) Lesser
C) The same
D) Zero
Answer: B – Orbital speed decreases as orbital radius increases.
14. A satellite in low Earth orbit experiences weight:
A) Equal to its surface weight
B) Slightly less than its surface weight
C) Zero
D) Twice its surface weight
Answer: B – Gravity decreases slightly with altitude, so weight is slightly less.
15. Gravitational force is a conservative force. This means:
A) Work depends on path taken
B) Work done in a closed path is zero
C) Force is always constant
D) It only acts in circular motion
Answer: B – Work done by gravity over a closed path is zero.
16. Which quantity is conserved for a satellite in orbit with no external torque?
A) Angular momentum
B) Linear momentum only
C) Kinetic energy only
D) None
Answer: A – Angular momentum is conserved in central force motion.
17. The centripetal force required for circular orbit of radius rrr and speed vvv is:
A) mv2r\frac{mv^2}{r}rmv2
B) mr2v\frac{mr^2}{v}vmr2
C) v2mr\frac{v^2}{mr}mrv2
D) mv2rmv^2 rmv2r
Answer: A – Centripetal force formula is F=mv2rF = \frac{mv^2}{r}F=rmv2.
18. Gravitational acceleration ggg on a planet’s surface decreases with:
A) Increasing mass
B) Increasing radius
C) Increasing orbital period
D) Increasing satellite mass
Answer: B – g=GMR2g = \frac{GM}{R^2}g=R2GM; larger radius decreases ggg.
, 19. A satellite is launched to a higher circular orbit. Its kinetic energy:
A) Increases
B) Decreases
C) Remains same
D) Becomes zero
Answer: B – Higher orbit requires lower speed, so kinetic energy decreases.
20. For a satellite in circular orbit, total mechanical energy EEE is:
A) KE+PEKE + PEKE+PE
B) KE−PEKE - PEKE−PE
C) Zero
D) Twice the kinetic energy
Answer: A – Total energy is sum of kinetic and potential energy, negative for bound orbits.
21. The orbital radius of a satellite is doubled. The gravitational force:
A) Doubles
B) Halves
C) Reduces by factor of 4
D) Reduces by factor of 8
Answer: C – Force F∝1r2F \propto \frac{1}{r^2}F∝r21, so doubling radius reduces force 4×.
22. A satellite moves from low orbit to high orbit. Its potential energy:
A) Increases
B) Decreases
C) Remains same
D) Becomes negative
Answer: A – Gravitational potential energy U=−GMmrU = -\frac{GMm}{r}U=−rGMm
becomes less negative.
23. Which of the following correctly describes geostationary satellites?
A) Orbit above poles
B) Same angular speed as Earth
C) Orbital period 12 hours
D) Move faster than Earth’s rotation
Answer: B – Geostationary satellites stay above a fixed point on equator.
24. If a planet’s mass doubles while radius remains same, surface gravity:
A) Halves
B) Doubles
C) Quadruples
D) Remains same
Answer: B – g=GMR2g = \frac{GM}{R^2}g=R2GM, doubling mass doubles ggg.
25. Weightlessness experienced by astronauts in orbit occurs because:
A) Gravity is zero
B) They are in free fall
ANSWERS | VERIFIED ANSWERS PLUS RATIONALES | EXAM
ALREADY GRADED A+ | LATEST EXAM
1. Which of the following is a vector quantity?
A) Mass
B) Speed
C) Displacement
D) Temperature
Answer: C – Displacement has both magnitude and direction, unlike scalars.
2. Newton’s law of gravitation states that the gravitational force between two masses is:
A) Directly proportional to distance squared
B) Inversely proportional to distance squared
C) Directly proportional to distance
D) Independent of distance
Answer: B – F=Gm1m2r2F = \frac{G m_1 m_2}{r^2}F=r2Gm1m2, force decreases with the
square of distance.
3. The gravitational field strength ggg at the surface of a planet depends on:
A) Planet’s mass and radius
B) Planet’s density only
C) Satellite’s mass
D) Satellite’s orbital speed
Answer: A – g=GMR2g = \frac{GM}{R^2}g=R2GM, where MMM is mass and RRR is radius.
4. What is the escape velocity from a planet of mass MMM and radius RRR?
A) GMR\sqrt{\frac{GM}{R}}RGM
B) 2GMR\sqrt{\frac{2GM}{R}}R2GM
C) GM2R\frac{GM}{2R}2RGM
D) 2GM2GM2GM
Answer: B – Escape velocity ve=2GMRv_e = \sqrt{\frac{2GM}{R}}ve=R2GM.
5. A satellite moves in a circular orbit at constant speed. Its acceleration is:
A) Zero
B) Toward the center of the orbit
C) Tangential to the orbit
D) Opposite the velocity
Answer: B – Centripetal acceleration always points toward the center of the orbit.
6. The period of a satellite in orbit depends mainly on:
A) Its mass
B) Mass of the central body
,C) Shape of the satellite
D) Its velocity only
Answer: B – Using T2∝r3/GMT^2 \propto r^3/GMT2∝r3/GM, the period depends on the central
mass.
7. The force keeping a planet in orbit around the Sun is:
A) Magnetic force
B) Gravitational force
C) Centripetal force only
D) Nuclear force
Answer: B – Gravity acts as the centripetal force keeping the planet in orbit.
8. Which of these quantities remains constant for a planet in circular orbit?
A) Orbital speed
B) Orbital radius
C) Kinetic energy
D) All of the above
Answer: D – In a circular orbit, speed, radius, and kinetic energy are constant.
9. Kepler’s third law states:
A) T2∝r3T^2 \propto r^3T2∝r3
B) T∝r2T \propto r^2T∝r2
C) r2∝T3r^2 \propto T^3r2∝T3
D) T3∝r2T^3 \propto r^2T3∝r2
Answer: A – The square of orbital period is proportional to the cube of orbital radius.
10. A geostationary satellite has a period of:
A) 12 hours
B) 24 hours
C) 7 days
D) 1 hour
Answer: B – Geostationary satellites orbit once per 24 hours, matching Earth’s rotation.
11. The gravitational potential energy of a satellite near Earth is:
A) 12mv2\frac{1}{2}mv^221mv2
B) mghmghmgh
C) −GMmr-\frac{GMm}{r}−rGMm
D) FdFdFd
Answer: C – Gravitational potential energy in orbit is U=−GMmrU = -
\frac{GMm}{r}U=−rGMm.
12. The kinetic energy of a satellite in a circular orbit is:
A) Equal to its potential energy
B) Half the magnitude of potential energy
C) Double the potential energy
,D) Zero
Answer: B – KE=−12UKE = -\frac{1}{2} UKE=−21U in circular orbit.
13. A satellite is in a higher orbit. Compared to a lower orbit, its orbital speed is:
A) Greater
B) Lesser
C) The same
D) Zero
Answer: B – Orbital speed decreases as orbital radius increases.
14. A satellite in low Earth orbit experiences weight:
A) Equal to its surface weight
B) Slightly less than its surface weight
C) Zero
D) Twice its surface weight
Answer: B – Gravity decreases slightly with altitude, so weight is slightly less.
15. Gravitational force is a conservative force. This means:
A) Work depends on path taken
B) Work done in a closed path is zero
C) Force is always constant
D) It only acts in circular motion
Answer: B – Work done by gravity over a closed path is zero.
16. Which quantity is conserved for a satellite in orbit with no external torque?
A) Angular momentum
B) Linear momentum only
C) Kinetic energy only
D) None
Answer: A – Angular momentum is conserved in central force motion.
17. The centripetal force required for circular orbit of radius rrr and speed vvv is:
A) mv2r\frac{mv^2}{r}rmv2
B) mr2v\frac{mr^2}{v}vmr2
C) v2mr\frac{v^2}{mr}mrv2
D) mv2rmv^2 rmv2r
Answer: A – Centripetal force formula is F=mv2rF = \frac{mv^2}{r}F=rmv2.
18. Gravitational acceleration ggg on a planet’s surface decreases with:
A) Increasing mass
B) Increasing radius
C) Increasing orbital period
D) Increasing satellite mass
Answer: B – g=GMR2g = \frac{GM}{R^2}g=R2GM; larger radius decreases ggg.
, 19. A satellite is launched to a higher circular orbit. Its kinetic energy:
A) Increases
B) Decreases
C) Remains same
D) Becomes zero
Answer: B – Higher orbit requires lower speed, so kinetic energy decreases.
20. For a satellite in circular orbit, total mechanical energy EEE is:
A) KE+PEKE + PEKE+PE
B) KE−PEKE - PEKE−PE
C) Zero
D) Twice the kinetic energy
Answer: A – Total energy is sum of kinetic and potential energy, negative for bound orbits.
21. The orbital radius of a satellite is doubled. The gravitational force:
A) Doubles
B) Halves
C) Reduces by factor of 4
D) Reduces by factor of 8
Answer: C – Force F∝1r2F \propto \frac{1}{r^2}F∝r21, so doubling radius reduces force 4×.
22. A satellite moves from low orbit to high orbit. Its potential energy:
A) Increases
B) Decreases
C) Remains same
D) Becomes negative
Answer: A – Gravitational potential energy U=−GMmrU = -\frac{GMm}{r}U=−rGMm
becomes less negative.
23. Which of the following correctly describes geostationary satellites?
A) Orbit above poles
B) Same angular speed as Earth
C) Orbital period 12 hours
D) Move faster than Earth’s rotation
Answer: B – Geostationary satellites stay above a fixed point on equator.
24. If a planet’s mass doubles while radius remains same, surface gravity:
A) Halves
B) Doubles
C) Quadruples
D) Remains same
Answer: B – g=GMR2g = \frac{GM}{R^2}g=R2GM, doubling mass doubles ggg.
25. Weightlessness experienced by astronauts in orbit occurs because:
A) Gravity is zero
B) They are in free fall
