# Question #81c60

Oct 12, 2017

The torque is $0.98 N \cdot m$.

#### Explanation:

The weight of the bob is $0.5 k g \cdot 9.8 \frac{m}{s} ^ 2 = 4.9 N$.

The component of that weight that is perpendicular to the pendulum rod is $4.9 N \cdot \cos 60 = 2.45 N$.

The distance from the pivot to the bob is 0.4 m.

Torque is calculated as follows
$\text{Torque" = "Perpendicular force"*"lever length}$
$\text{Torque} = 2.45 N \cdot 0.4 m = 0.98 N \cdot m$

I hope this helps,
Steve