Problem 1

Masses

m_1=2

kg and

m_2=3

kg hang from the ends of a light inextensible string passing over a fixed frictionless pulley of negligible radius. The system is released from rest and the string remains taut. Take

g=10

m/s

^2

and choose each mass's direction of motion as positive. (a) Determine the direction and acceleration of each mass. (b) Find the string tension. (c) Find their speed after moving

s=0.80

m from rest, and check it by energy conservation.

problems.proof.stepOf

problems.proof.prevStep problems.proof.nextStep

m_2g-T=m_2a,\quad T-m_1g=m_1a

problems.proof.analysis

Project forces along each mass's motion. For descending $m_2$ , weight minus tension equals $m_2a$ ; for rising $m_1$ , tension minus weight equals $m_1a$ .