Q:

A 10 meter long ladder is supported by a vertical wall. If its base moves at a rate of 2 m/s horizontally in the opposite direction to the wall, determine the rate of change of the top of the ladder when its base is 8 meters from the wall.

Accepted Solution

A:
$x^2+y^2=100\to2x\cdot\frac{dx}{dt}+2y\cdot\frac{dy}{dt}=0\to2\cdot8+2\cdot6\cdot\frac{dy}{dt}-0\to\frac{dy}{dt}=\frac{16}{3}\frac{m}{s}$