A motor of mass M is supported by springs with an equivalent

A motor of mass M is supported by springs with an equivalent spring constant k. The unbalance of its rotor is equivalent to a mass m located at a distance r from the axis of rotation. Show that when the angular velocity of the rotor is ωf, the amplitude xm of the motion of the motor is where ωn = ˆšk/M.

r(m/ M)(,lw, 1-(0,/0 Xm