Hooke's law describes a certain light spring of unstretched length 32.0 cm. When one end is attached to the top of a door frame and a 5.40-kg object is hung from the other end, the length of the spring is 46.5 cm.
(a) Find its spring constant.
kN/m
(b) The load and the spring are taken down. Two people pull in opposite directions on the ends of the spring, each with a force of 160 N. Find the length of the spring in this situation.
A 2.1 103-kg car starts from rest at the top of a 5.9-m-long driveway that is inclined at 19° with the horizontal. If an average friction force of 4.0 103 N impedes the motion, find the speed of the car at the bottom of the driveway.
m/s
1 answer