Question

A fly wheel is accelerated uniformly from rest and rotates through 5 rad in the first second. The angle rotated by the fly wheel in the next second, will be:

• A. 7.5 rad
• B. 15 rad
• C. 20 rad
• D. 30 rad

Answer 1

Answer: (B)

15 rad

Answer 2

$θ_1 = \frac{1}{2} α(2\times 1-1) = 5 \;rad$

⇒ $α = 10\; rad/sec^2$

So $θ_2 = \frac{1}{2} \times α(2\times 2-1) = 15 \;rad$