A pulley is in the form of a uniform solid cylinder of radius 7cm and mass 2kg. One end of a very light rope is fixed to wind the pulley and the other end is free. When we pull the free end of the rope the pulley starts rotating from rest and accelerates uniformly. If the angular acceleration is 100rad/s so the
constant torque that we exert on the pulley through the rope is:
Chọn một:
a.
0.49 N. m
b.
7 N. m
C.
200N. m
d.
49 N. m