The instantaneous angular position of a point on a rotating wheel is given by the equation θ(t) = 2t³ – 6t². The torque on the wheel becomes zero at

Options

(a) t = 1 s
(b) t = 0.5 s
(c) t = 0.25 s
(d) t = 2 s

Correct Answer:

t = 1 s

Explanation:

When angular acceleration is zero then torque on the wheel becomes zero.
θ(t) = 2t – 6t
dθ / dt = 6t – 12t
= dθ / dt = 12t – 12 = 0
t = 1 s