A particle moves along a circle of radius ( 20 ) m with constant tangential acceleration. If the velocity of the particle is 80 m/s at the end of the second revolution after motion has begun, the tangential acceleration is
- 40 m/s2
- 640 m/s2
- 160 m/s2
- 40 m/s2
Answer
(1) 40 m/s2
Solution
Distance covered along the circle in 2 revolutions:
s = 2 2 r
= 4 20
= 80 m
With constant tangential acceleration from rest: v2 = u2 + 2at s
⇒ (80)2 = 0 + 2at 80
⇒ at = 6400160
= 40 m/s2
Answer: (1)