A car drives around a circular curve of radius 5 m at 10 m/s. What is its centripetal acceleration?
Answer and explanation
Correct answer: A. 20 m/s^2
- Step 1: Centripetal acceleration is a = v^2 / r.
- Step 2: a = 10^2 / 5 = 20 m/s^2.
Answer
20 m/s^2.
Why not the others: The speed is squared and divided by the radius; v/r, v^2 r and v r are different quantities.
Practise more Mechanics.
Free questions with an explanation for every one, and full timed Državna Matura (Montenegro) mock tests.
More Mechanics questions
- A car starts at 10 m/s and accelerates uniformly at 5 m/s^2 for 6 s. What is its final speed?
- An object moves with initial speed 4 m/s and constant acceleration 2 m/s^2. How far does it travel in 5 s?
- A 10 kg block is pulled along a rough floor by a horizontal force of 30 N. Friction is 10 N. What is the block's acceleration?
- A frictionless slide is 3.2 m high. A child starts from rest at the top. Taking g = 10 m/s^2, what is the child's speed at the bottom?
- A 2 kg cart moving at 6 m/s hits a 1 kg cart at rest and the two stick together. What is their common speed afterwards?
- What is the gauge pressure due to water at a depth of 2 m? (density 1000 kg/m^3, g = 10 m/s^2)