A)
A mass weighing 16 pounds stretches a spring 8/3 feet. The massis initially released from rest from a point 4 feet below theequilibrium position, and the subsequent motion takes place in amedium that offers a damping force that is numerically equal to 1/2the instantaneous velocity. Find the equation of motion x(t) if themass id riven by an external force equal to f(t) = 20 cos 3t useg=32 ft/s^2 for the acceleration due to gravity)
B)
A mass of 1 slug, when attached to a spring stretches it 2 feetand then comes to rest in the equilibrium position starting at t=0an external force equal to f(t)=6 sin 4t is applied to the system.Find the equation of motion if the surrounding medium offers adamping force that is numerically equal to 8 times theinstantaneous velocity. use g=32 ft/s^2 for the acceleration due togravity.
