Pearson Edexcel International GCSE (9–1) · PHYSICS · Chapter
Units (Astrophysics)
16 practice questions
Practice questions
11–16 of 16
Question 11
2 marks · Normal
Answer and see the solution →A student says a planet's mass is '6000 kg'. What is wrong with this answer in the context of planetary science? Explain your answer.
Question 12
2 marks · Normal
Answer and see the solution →A planet has a gravitational field strength of 15 N/kg. What is the weight of a 4 kg object on this planet?
Question 13
3 marks · Normal
Answer and see the solution →A moon has a mass of 7.3 × 10^22 kg. It is in orbit around its planet.
(a)[1 mark]State the SI unit for mass.
(b)[2 marks]Explain why the gravitational force between the moon and its planet is much greater than the force between two footballs of similar size.
Question 14
2 marks · Normal
Answer and see the solution →State two quantities in astrophysics that use the newton (N) as their SI unit. Give one example for each.
Question 15
3 marks · Normal
Answer and see the solution →Complete the table below by writing the SI unit for each quantity.
Quantity SI unit (give symbol) Length Speed Mass (a)[1 mark]Length
(b)[1 mark]Speed
(c)[1 mark]Mass
Question 16
2 marks · Normal
Answer and see the solution →Explain why the unit of speed in astrophysics is usually written as m/s rather than km/h. Give one reason.