The angular velocity of a wheel increases from 100 rps to 300 rps in 10 seconds. The number of revolutions made during that time is

Options

(a) 600
(b) 1500
(c) 1000
(d) 2000

Correct Answer:

2000

Explanation:

Assuming constant angular acceleration,
α=2πx300-2πx100/10
=2πx200/10
=40 π radius/s²
ω²f-ω²i=2α.θ
θ=4π²(90000-10000)/2×2πx20
=2π(80000)/40
=2πx2000
.·. Total number of revolutions=2000.