MCQ
A constant torque acting on a uniform circular wheel changes its angular momentum from $A_0$ to $4 A_0$ in $4$ seconds. The magnitude of this torque is ...........
- ✓$\frac{3 A_0}{4}$
- B$A_0$
- C$4 A_0$
- D$12 A_0$
✓
Answer
Correct option: A.
$\frac{3 A_0}{4}$
a
(a)
(a)
$\tau=\frac{\Delta L}{\Delta t}$
$\tau=\frac{4 A_0-A_0}{4}=\frac{3 A_0}{4}$
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