Question

Answer With Solution
A particle is moving with a constant speed v
in a circle. What is the magnitude of average
velocity after half rotation?
(a) 2v (b) 2v/π (c) v/2 (d) v/2π​​

Answer 1

Answer:

(b)2v/pi

Explanation:

Let the radius of circle is R and time taken to cover half rotation is T

Speed = distance /Time

distance = half rotation = circumference of semi circle= R×Pi

V= RPi÷T -------eqn (i)

Velocity = displacement / time

Velocity = 2R/T ------eqn (ii)

Now multiply eqn i with 2 and divide it by Pi

2V÷Pi = 2Rpi÷T pi

so we get 2V÷Pi = 2R/T

so 2V/Pi= Velocity