Originally Posted by

**tilterino** Hi could someone please help show me how to solve the following two questions, I've spent a couple of hours at these without success.

1)

A search light is 225m from a straight waal. As the beam moves along the wall, the angle between the beam and the perpendicular to the wall is increasing at a rate of 1.5 degree/sec. How fast is the length of the beam increasing when it is 315m long?

The diagram indicates the beam on the ground pointing up to the perpendicular wall and moving across the x axis.