Angular acceleration and Torque when rod reaches vertical position?? A rod (mass 1.30 kg, length .670 m) attached to a frictionless axis is released from rest in the horizontal position. What is the magnitude of the torque and angular acceleration when the rod has reached the vertical position? I know at horizontal position (immediately after release) Torque = FR = mg(L/2)= 4.27n-m and torque = I∂ giving ∂ = 21.9 rad/s^2...but how do I solve for when it hits vertical position...? Please help!