Question

Problem 14. A 7-kg and a 11-kg box are suspended by a large pulley that has a mass of 3 kg and a radius of 0.15 m. The masses start 3.5 m apart, and the system is released from rest. What is the speed of the boxes when they pass one another? 11kg: 3.5m 7kg

Answer 1

3.5m Let the acceleration of system is a. and Tension in string is T, and T. Hence, appaying Newton's law, T-79=79 0 "g-T=hla - D and For pulley, T = IL 7 Ra=Ra t =IL → TR-TR=jme? (0) TH-T, = Ima T-T, = 4x30 T - Ti = a eqn and adding Ti - T +49 = 189 & T-T, = 49-18a - from ean . and a = 49-18 a 3+ 180 A -- -- 13.5m. talder meeting boxes it travel a distance * → 9% = 35 3o = Sem In = 3.5 W

10 Hence the speed of bobes when they pass one another applying equation of motion. Taval 12=42 +298 - v2 = 02 + 2x & g x 35 > 202 = 7.63589 7 V = 2.65 m/8