Question

The exterior of a lamp post is to be painted. The lamp post is a 14-foot tall cylinder with a diameter of 18 inches. Since the base is on the ground and the top is covered by a floodlight, you will not need to paint these pieces. What is the area that needs to be painted?

Answer 1

To find the surface area that needs to be painted, we first need to calculate the lateral surface area of the cylinder. The formula for the lateral surface area of a cylinder is 2πrh, where r is the radius and h is the height of the cylinder.

First, we need to convert the diameter to radius by dividing it by 2:
Radius = 18 inches / 2 = 9 inches

Now, we can calculate the lateral surface area:
Lateral Surface Area = 2π(9 inches)(14 feet * 12 inches/foot) = 2π(9)(168) = 3024π square inches

Therefore, the area that needs to be painted on the lamp post is approximately 9506.94 square inches.