1. You find a 30 N box on the middle of a set of stairs and carry the box up a flight of stairs to a deck, raising its elevation by 5 m. Then you drop the box off of the deck. As the box reaches its original level (the box is moving when it reaches the original level because it has not reached the ground), its kinetic energy is
| The kinetic energy of the box cannot be determined. |
2. A 2 kg car moving towards the left at 4 m/s collides head on with an 8 kg car moving towards the right at 2 m/s, and they stick together. After the collision, the velocity of the combined bodies is
0.8 m/s towards the right.
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0.8 m/s towards the left.
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2.4 m/s towards the right.
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2.4 m/s towards the left.
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3. A 0.12 kg bullet traveling at 1129 mph hits a 6 kg block of wood and stays in the wood. What is the velocity (speed) of the wood block immediately after the bullet hits it?
4. The catapult on an aircraft carrier can take an aircraft from 0 to 197 mph in 10 seconds, at which time the aircraft launches. Express the launch speed in SI units (meter-kilogram-second (MKS) system - not km/hr).
5. An aircraft starts at rest and is accelerated at 7.8 m/s2 for 9 seconds, at which time the aircraft launches. What is the distance traveled from the starting point to the launch point? Assume the acceleration is constant.
6. It takes an elevator 2.1 minutes to raise a vehicle with a weight of 4079 N from the floor to a height of 9 meters. What size (power) motor (in watts) does it take to do the job? Hint: this is a multiple step problem in which you must derive the variables needed to solve for problem in step one and then apply those values to the final solution of the problem. Watch your units.
7. A pilot will black out if experiencing a centripetal acceleration of greater than 5g's. An F-16 going 344 mph enters a tight turn of radius 320 m. The pilot in this case is experiencing how many g's? You do not need to enter units for this problem.
8. A 201.7 kg satellite is in a circular orbit of 22,000 miles (35,405,000 m) in radius. The force keeping the satellite in orbit is 42.4 N. What is the velocity (speed) of the satellite?
9. The catapult on an aircraft carrier can take an aircraft weighing 300,000 N from 0 to 180.6 mph in 8.6 seconds, at which time the aircraft launches. What is the acceleration of the aircraft when it launches? Express your answer in the MKS system of units.
10. An aircraft weighing 937 N is accelerated at 9 m/s/s for 9 seconds, at which time the aircraft launches. How much work was done on the aircraft? The acceleration is constant.
Hint: This is a multiple step problem in which you must derive the variables needed (mass and distance under constant acceleration) in step one and then apply those values to the final solution of the problem in step two, that is calculate the work done.