Question

In a lab involving a pulley, a block, and a spring scale to measure force, imagine the following scenario:

You tie one end of a meter-long string to something fairly solid like a doorknob. You put the pulley over this string, so the sheave of the pulley is on top of the string, and the other end of the string goes straight back up. Then, the block is hung directly from the pulley.

Q1: Predict, using Newton’s second law and assuming a mass of 2.0 kg, what a spring scale that is attached to the free end of the string should read.

Q2: If the ends of the string in this scenario were not vertical, but instead made an angle of 30-degrees with respect to vertical, and the pulley and block together had a mass m, what would be the reading on a spring scale attached to the free end of the string the pulley is on?

Answer 1