20.5.2
The mechanism moves in a vertical plane. The kinetic energy T = 2φ2, the generalized force corresponding to the coordinate is equal to Qφ = M - 8cosφ. Determine the moment M of the force pair applied to the crank OA, when the angular acceleration φ = 2 rad / s2 and the angle φ = 0.25π rad. (Answer 13.7)