Question 31: Centre of Mass and Rotational Motion

Question

The wheel of a car, accelerated uniformly from rest, rotates through 5 radians during the first second. The angle (in radians) rotated during the next second is

Accepted Answer

From 2nd equation of rotational motion,
$	heta  = {\omega _0}t + {1 \over 2}\alpha {t^2}$
Given, $	heta$ = 5 rad, t = 1s, $\omega$
0
= 0
Substituting all these values in above equation, we get
$5 = 0 + {1 \over 2}\alpha {(1)^2} \Rightarrow \alpha  = 0$ rad/s
2
The angle rotated by wheel of car during first two seconds,
${	heta _2} = 0 + {1 \over 2} + \alpha {t^2} = {1 \over 2} 	imes 10 	imes {2^2} = 20$ radians
Hence, angle rotated during the 2nd second
= $	heta$
2
= 0
= 2 $-$ 5 = 15 radians

Answer

15

Answer

7.5

Answer

12.5

Answer

20

Centre of Mass and Rotational Motion

The wheel of a car, accelerated uniformly from rest, rotates through 5 radians during the first second. The angle (in radians) rotated during the next second is

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