posted by Ricky on .
1. How far (in meters) must a 600 kg pile driver fall, if it is to do 14000 J of work?
2. A spring whose spring constant is 150 N/m is compressed 0.800 m. What speed (in meters/second) can it give to a 0.600 kg ball when released?
3. A 550 N crate rests on the floor. How much work in joules is required to move it at constant speed 4.0 m along the floor, against a friction force of 140 N?
4. What is the minimum work in joules needed to push a 1710 kg car 74.0 m up a 12.5 degree incline? (Ignore friction.)
5. How much work in joules must be done to stop a 3000 kg car traveling at 150 km/hr?
6. A 1620 kg car rolling on a horizontal surface has a speed of 70 km/hr when it strikes a horizontal coiled spring and is brought to rest in a distance of 5.5 m. What is the spring constant (in N/m) of the spring? (Ignore nonconservative forces such as friction.)
7. A spring has a spring constant "k" of 160 N/m. How much must this spring be compressed (in meters) to store 70 J of energy?
8. Tarzan is running at a top speed of 5.0 m/s and grabs a vine hanging vertically from a tall tree in the jungle. How high (in meters) can he swing upward?
9. An object slides down a frictionless 33 degree incline whose vertical height is 87.0 cm. How fast is it going in meters/second when it reaches the bottom?
10. A 33 kg child descends a slide 7.8 m high and reaches the bottom with a speed of 3.30 m/s. How much thermal energy (in joules) due to friction was generated in this process?
11. Two railroad cars, each of mass 6800 kg and traveling 80.0 km/hr, collide head-on and come to rest. How much thermal energy in joules is produced in this collision?
You need to know just a few things.
In a gravitational field of strength g, potential energy = m g h
Kinetic energy = (1/2) m v^2
energy stored in a spring = (1/2) k x^2
work done = force times distance moved in the direction of the force.