1. A force of 25 N pushes a curling rock, which is initially at rest, a distance of 1 m along frictionless ice. What is the final kinetic energy of the rock? 2. An adult exerts a force of 26 N to pull a child across the snow on a sled. The pull-rope attached to the sled is at an angle of 21 above the horizontal. Ignoring friction, how much work is done in pulling the sled 250 m? 3. A wooden block is pulled 5 m [E] along a horizontal floor with a constant force of 12 N [E60 above the floor]. Find the change in kinetic energy if the floor is frictionless 4. The combined mass of a roller-coaster car and riders is 500 kg. The car starts from rest at the top of a hill 15 m high and proceeds through a loop 6 m high. Find the speed of the car at the top of the loop. 5. A 2 kg cart is pulled forward with a spring by a force of 5 N [E]. The elastic constant of the spring is 25 N/m. Find the acceleration of the cart and the extension of the spring. 6. A mass of 2 kg rotates at 1 m/s in a horizontal circle on a table at the end of a spring with an elastic constant 50 N/m. If the original length of the spring is 2 m, find the extension of the spring. 7. A 2 kg mass is suspended from the ceiling of an elevator by a spring with elastic constant of 50 N/m. Find the extension of the spring when the elevator accelerates up at 3 m/s2. 8. An object of mass 10 kg is dropped from a height of 2 m onto a spring. If the elastic constant of the spring is 50 N/m, find the maximum compression of the spring. 9. A 1500 kg car accelerates from rest at 4 m/s/s for 6 s. What momentum does it acquire in that time