JEE Main · 2024 · 09 Apr 2024 · Shift 1 · Rotational Mechanics

A string is wrapped around the rim of a wheel of moment of inertia

0.40 kgm^{2}

and radius 10 cm. The wheel is free to rotate about its axis. Initially the wheel is at rest. The string is now pulled by a force of 40 N. The angular velocity of the wheel after 10 s is

x rad / s

, where

x

is ____.

Answer: 100

Solution

τ = F R = I α \Rightarrow α = \frac{40 \times 0.1}{0.40} = 10

rad/s

^{2}

ω = α t = 10 \times 10 = 100

rad/s, so

x = 100

JEE Main · 2024 · 09 Apr 2024 · Shift 1 · Integer answer

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