A ladder long leans against a wall

MATHEMATICS · Subjective · CBSE · Mathematics · Applications of Derivatives · Applications of Derivatives

Problem

A ladder

13\,\text{m}

long leans against a wall. The foot of the ladder is pulled along the ground away from the wall at the rate of

1.5\,\text{m/s}

. How fast is the angle

\theta

between the ladder and the ground changing when the foot of the ladder is

12\,\text{m}

away from the wall?