A2290 kg car traveling at 10.5 m/s collides with a 2780 kg car that is initially at rest at the stoplight. the cars stick together and move 2.80 m before friction causes them to stop. determine the coefficient of kinetic friction

Aplayground slide is 8.80 ft long and makes an angle of 25.0° with the horizontal. a 63.0-kg child, initially at the top, slides all the way down to the bottom of the slide. (a) choosing the bottom of the slide as the reference configuration, what is the system's potential energy when the child is at the top and at the bottom of the slide? what is the change in potential energy as the child slides from the top to the bottom of the slide? (include the sign of the value in your answer.)