(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Blocks A and B have masses 11 kg and 5 kg, respectively, and they are both at a height h = 2m above the ground when the system is released from rest. Just before hitting the ground block A is moving at a speed of 3 m/s. Determine a.) the amount of energy dissipated in friction by the pulley, b.) the tension in each portion of the cord during the motion.

(blocks A and B are hanging at the same height attached by a cable that passes through a pulley above them)

2. Relevant equations

KE = 1/2mv^{2}

PE = mgz

F = ma

3. The attempt at a solution

E_{A}= mgz

E_{A}= (11 kg)(9.81 m/s^{2})(2 m)

E_{B}= mgz

E_{B}= (5 kg)(9.81 m/s^{2})(2 m)

KE_{A}at y = 0 m

KE_{A}= 1/2(11 kg)(3 m/s)^{2}

KE_{A}= 49.5 J

The answer in the book for a.) is 45.7 J

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Dynamics: Determining amount of energy dissapated by a pulley

**Physics Forums | Science Articles, Homework Help, Discussion**