Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Astrophysics
156 practice questions
Topics covered
Practice questions
21–30 of 78 · Easy
Question 21
3 marks · Easy
Answer and see the solution →A planet and an artificial satellite are shown below.
Planet and satellite orbit. (a)[1 mark]Draw an arrow on the diagram to show the direction of the force acting on the satellite.
(b)[2 marks]Explain why this force is always directed towards the planet.
Question 22
2 marks · Easy
Answer and see the solution →Describe two differences between the orbit of a comet and the orbit of a planet.
Question 23
1 mark · Easy
Answer and see the solution →How long does it take the Moon to orbit the Earth once? Give your answer in days.
Question 24
1 mark · Easy
Answer and see the solution →State the unit for gravitational field strength.
Question 25
1 mark · Easy
Answer and check →Which planet has the highest gravitational field strength among the following?
- A.Mars
- B.Venus
- C.Jupiter
- D.Mercury
Question 26
1 mark · Easy
Answer and see the solution →State the two factors that affect the gravitational field strength at the surface of a planet.
Question 27
2 marks · Easy
Answer and see the solution →A satellite orbits a planet at a constant radius of 10,000 km and completes one orbit every 20,000 seconds. Calculate its average orbital speed in km/s. Give your answer to 2 significant figures.
Question 28
2 marks · Easy
Answer and see the solution →Explain why satellites in low orbits travel at a higher speed than satellites in high orbits around Earth.
Question 29
3 marks · Easy
Answer and see the solution →The table shows some information about two planets:
Planet information Planet Mass (Earth=1) Radius (Earth=1) Planet A 1.5 1.0 Planet B 1.0 2.0 (a)[2 marks]Which planet has the higher gravitational field strength at its surface? Explain your answer.
(b)[1 mark]Which planet would an object weigh less on? Give a reason.
Question 30
3 marks · Easy
Answer and see the solution →A moon orbits its planet at a radius of 450,000 km. It takes 40 days to complete one orbit.
(a)[1 mark]Convert the orbital period into seconds.
(b)[2 marks]Calculate the average orbital speed of the moon in km/s. Give your answer to 2 significant figures.