In: Physics
A 1.71 kg ball and a 3.27 kg ball are connected by a 1.76 m long rigid, massless rod. The rod is rotating clockwise about its center of mass at 24 rpm. What torque will bring the balls to a halt in 10.06 s? (Give an absolute value of torque.)
first, to calculate the center of mass
The formula for the moment of inertia [I] of an object consisting of particles with masses [m_i] , at distances [r_i] from the rotation axis is
knowing that the absolute value of torque is given by
, where (I=moment of inertia = Average angular acceleration)
we need to calculate the average angular acceleration using angular velocity
,where ''w'' is given by w=2f and t=time
using the following convertion factor 1Hz=60rpm, it follows that
the absolute torque is
note: this torque is exerted counterclockwise