Circular motion and centripetal force

Question 1

A 0.5 kg object moves in a circle of radius 1 m at 4 m/s. What centripetal force is needed, in N? (F = m v² ÷ r)

Answer N

Question 2

Friction between the tyres and the road provides 10800 N of centripetal force for a 1500 kg car on a bend of radius 20 m. What is the car's speed, in m/s?

Answer m/s

Question 3

A car goes round a bend twice as fast. How does the centripetal force needed change?

• A. it becomes four times larger
• B. it halves
• C. it doubles
• D. it stays the same

Question 4

A 0.5 kg object moves in a circle of radius 0.5 m at 20 m/s. What centripetal force is needed, in N? (F = m v² ÷ r)

Answer N

Question 5

Friction between the tyres and the road provides 1280 N of centripetal force for a 1000 kg car on a bend of radius 50 m. What is the car's speed, in m/s?

Answer m/s

Question 6

What provides the centripetal force for the Moon orbiting Earth?

• A. the Moon's engines
• B. magnetism
• C. friction with space
• D. Earth's gravitational pull

Question 7

A 1 kg object moves in a circle of radius 1 m at 10 m/s. What centripetal force is needed, in N? (F = m v² ÷ r)

Answer N

Question 8

Friction between the tyres and the road provides 2812.5 N of centripetal force for a 1000 kg car on a bend of radius 80 m. What is the car's speed, in m/s?

Answer m/s

Question 9

What provides the centripetal force for the Moon orbiting Earth?

• A. Earth's gravitational pull
• B. friction with space
• C. the Moon's engines
• D. magnetism

Question 10

A 60 kg object moves in a circle of radius 10 m at 10 m/s. What centripetal force is needed, in N? (F = m v² ÷ r)

Answer N

Question 11

Friction between the tyres and the road provides 1500 N of centripetal force for a 1500 kg car on a bend of radius 25 m. What is the car's speed, in m/s?

Answer m/s

Question 12

A hammer thrower lets go of the hammer. Which way does it fly?

• A. straight outwards from the centre
• B. towards the centre
• C. along a tangent to the circle at the point of release
• D. in a smaller circle

Question 13

A 60 kg object moves in a circle of radius 10 m at 2 m/s. What centripetal force is needed, in N? (F = m v² ÷ r)

Answer N

Question 14

Friction between the tyres and the road provides 1920 N of centripetal force for a 1500 kg car on a bend of radius 50 m. What is the car's speed, in m/s?

Answer m/s

Question 15

A car goes round a bend twice as fast. How does the centripetal force needed change?

• A. it halves
• B. it doubles
• C. it stays the same
• D. it becomes four times larger

Question 16

A 2 kg object moves in a circle of radius 10 m at 10 m/s. What centripetal force is needed, in N? (F = m v² ÷ r)

Answer N