The centripetal acceleration of a car traveling at constant speed around a frictionless circular track is:
Correct answer: B. Constant magnitude but the varying direction
- A. Zero
- B. Constant magnitude but the varying direction
- C. Constant direction but the varying magnitude
- D. Varying magnitude and direction
Explanation
Centripetal acceleration is the acceleration experienced by an object moving in a circular path. It always points toward the centre of the circle and is perpendicular to the velocity of the object. The magnitude of centripetal acceleration is given by the formula a = v2/r, where v is the velocity of the object and r is the radius of the circular path. In the case of a car travelling at a constant speed around a frictionless circular track, the car's velocity remains constant (magnitude and direction) because speed is defined as the magnitude of velocity. However, the direction of velocity is constantly changing as the car moves along the circular path. Since centripetal acceleration is always directed towards the centre of the circle and perpendicular to the velocity, its magnitude remains constant, but its direction continuously changes to match the changing direction of the car's velocity.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Acceleration
Acceleration measures the rate at which velocity changes with time, including changes in speed, direction or both. Work includes average and instantaneous acceleration, the relation a = Δv/Δt, uniform acceleration equations, and interpreting velocity time and displacement time graphs, with acceleration carefully distinguished from velocity.
Practise Force and Motion
1,416 free Force and Motion MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Acceleration questions
A car at rest starts moving with linear uniformly increasing velocity. After 20 seconds, it attains the maximum velocity of 80 m/s. What is the distance covered during this time interval?
The acceleration is a _.
What is the shape of velocity, time graph for constant acceleration ?
The net acceleration of a particle in circular motion is:
A stone tied to the end of a string 80cm long is whirled in a horizontal circle with a constant speed. If the same stone makes 14 evolutions in 25 sec, what is the magnitude of the acceleration of the stone?
Find the magnitude of the centripetal acceleration of a particle on the tip of a fan blade of length 0.30 metre, rotating at 1200 rev/minute