As shown in the figure, a 1.5 kg box is held at rest against a spring with a force constant k = 700 N/m that is compressed a distance d. When the box is released, it slides across a surface that is frictionless, except for a rough patch that has a coefficient of kinetic friction k = 0.40 and is 6.0 cm in length. If the speed of the box is 2.9 m/s after sliding across the rough patch, determine the initial compression d (in cm) of the spring.

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.