Question

Problem: A pulley, consists of a disk of radius R=0.2 m and mass M= 50 kg is mounted on a nearly frictionless axle. A string is wrapped lightly around the pulley, and you pull on the string with a constant force, F = 100 N. If the pulley starts from rest, what is the angular speed at a time At = 1 s later? Assume that the string does not slip on the pulley. Note: Moment of inertia of a disk about an axis through its center of mass is Liek = (1/2) MR W = 0 2 M = 50 kg F= 100N F= 100N 19.AO 20 rad/s BO 25 rad/s CO 15 rad/s DO 10 rad/s EO None of the above

Answer 1

solution Moment of inertia of the fully = I I= I MR2 = L x 50 x 10.21% = loo kg m2 Torque on the Pally = ł. T = FXR = 100 x 0.2= 20 Nm. so the angular acceleration at the Pully = x= 1 = 20 1 = 20 nad 12 so angular speed cef Pally at t=1s = d e = at two = 2011 to = 20 rad/5 TA- ☺ 20 radls The correct answer is