The Pulley Problem The Pulley Problem was a problem we did in class. It had to do with two pulleys and a belt. The question was: How long was the belt that went around the pulley? The radius of the pulleys were given along with the length of the space between the pulleys as shown in the diagram below: In order to find out how long the belt was first we have to find out the circumference of the pulleys: C=2 r C=2 x 3.14 x 6 cm C=6.28 x 6 cm C=37.68 Then you have to divide that by two to equal: 18.84 2 )37.68 This solves where the belt contacts the pulley.

Next solve the distance where the belt contacts the pulley. The pulleys are 25 cm apart but the belt needs 6 more cm on each side before it can reach the pulley.

So therefore 6 cm + 25 cm + 6 cm = 37 cm is an appropriate sentence. Add where the belt contacts the pulley and where it is stretched between the pulleys.

2 x 18.84 cm + 2 x 37 cm = 111.68 That is how you get your answer to the pulley problem.