Question

*100 point ques*

A body revolves with constant speed v in a circular
path of radius r. The magnitude of its average
acceleration during motion between two points in
diametrically opposite direction is
(1) Zero
(2)v^2/r
(3)2v^2/pi r
(4)v^2/2r

with explanation please​

Answer 1

Answer:

2v^2/pi×r

Explanation:

Average acceleration is change in velocity by either change in its magnitude or change in its direction. But here for a uniform circular motion magnitude being constant (speed) direction changes which causes change in acceleration and by definition from NCERT acceleration is change in velocity during the course of overall interval. Therefore following ans should be the quick answer for the given question : Here v1 and v2 are two velocities say at point P and Q diametrically opposite points.

Answer 2

Answer:

solved

Explanation:

Acceleration is defined as rate of change of velocity.

Speed of the body is given to be constant. At diametrically opposite points velocity will be in opposite direction.

We can choose coordinate axes so that these velocities are  -v , v

change in velocity = v - (-v) = 2v

Time taken to move half circumference  = π R/v

a = 2v ÷ π R/v = 2v²/πR