A 50-cm-long spring is suspended from the ceiling. A 230 g mass is connected to the end and held at rest with the spring unstretched. The mass is released and falls, stretching the spring by 28 cm before coming to rest at its lowest point. It then continues to oscillate vertically. a. What is the spring constant? (K=)
b. What is the amplitude of the oscillation?
c. What is the frequency of the oscillation?

A60-kg box is being pushed a distance of 6.8 m across the floor by a force p with arrow whose magnitude is 162 n. the force p with arrow is parallel to the displacement of the box. the coefficient of kinetic friction is 0.24. determine the work done on the box by each of the four forces that act on the box. be sure to include the proper plus or minus sign for the work done by each force. (the floor is level and horizontal. forces that act on the box: pushing force p, frictional force f, normal force n, and weight mg.)