Question

A torque of 50 Nm acts on a body for 8 seconds which is initially at rest. The change in its angular momentum is

• A. 400 kgm\(^2\)/s
• B. 600 kgm\(^2\)/s
• C. 1000 kgm\(^2\)/s
• D. 800 kgm\(^2\)/s

Hint:

The change in angular momentum is directly proportional to the torque and the time for which the torque acts.

Answer 1

The Correct Option is A

Step 1: Using the formula for angular momentum.
The change in angular momentum \( \Delta L \) is given by the product of torque \( \tau \) and time \( t \): \[ \Delta L = \tau \cdot t \] Where: - \( \tau = 50 \, \text{Nm} \), - \( t = 8 \, \text{s} \). Thus, the change in angular momentum is: \[ \Delta L = 50 \times 8 = 400 \, \text{kgm}^2/\text{s} \] Thus, the correct answer is (A) 400 kgm\(^2\)/s.