Exp Physics review Problems --* these problems are to get you thinking about the topics covered over the semester, they are not intended to be an exhaustive list of things you will see on the exam. Test, quiz, and homework problems/topics will also be on it and should be reviewed.

  1. How many inches are in a 0.08 km?
  1. How many ft is 40m ?
  1. How many Coulombs are 3 billion electrons?
  1. Using the x axis as 0 calculate and label the x and y components for A=10 @ -30
  1. Using the x axis as 0 calculate and label the x and y components for B = 10 @ 90
  1. A skier shoots perfectly horizontally off a cliff with a speed 30 m/s. The cliff is 20 m off the ground. What are the following values?

xi

yi

vxi

vyi

ax

ay

Write the x and y equations of motion for the skier

At what time does he hit the ground?

How far away from the cliff does he land?

  1. A ball is shot off at 45 at 20 m/s from a platform that is 3m off the ground. How long will it be in the air? Where will it hit the ground? (write the x and y equations first)
  1. A 1225 kg car is going 105km/hr and stops in 4 seconds. How much and in what direction is the force that stops it? (calculate the acceleration first) How far has it moved during this time?
  1. You swim perpendicular to a river that is flowing at 10 m/s. Relative to the water you swim at 3m/s across

Draw and label the velocity vectors showing that your velocity relative to the water plus the velocity of the water adds up to your velocity relative to the shore. vyw + vws =vys

Calculate your velocity relative to the shore and give the answer in magnitude and direction.

  1. The 200kg wagon is pulled with a 100N force at a 60 angle. It moves forward 5m. How much work was done? How fast is it now going if it started from rest?

60

  1. The pull force for a pulley is 40 N. Pulling the rope through 2m lifts the 32 kg load 0.25 m. Sketch it and a figure out the:

work input

efficiency

If the pulley system were 100% efficient what would the pull force be?

  1. A 200 kg box sits on the ice so there is no friction. It is pushed with a force of 30 N. What is its acceleration?
  1. The same 200 kg box is now on asphalt. The coefficient of friction between the box and road is 0.9. First calculate the normal force that he box pushes down on the road with, then calculate the force of friction that will be between the road and box. Calculate the acceleration if it is pushed with a force of 2000N

DRAW the FBD!!

  1. At 15 rpm a rock is swung around in a circle at the end of a 2m piece of string. What is its tangential velocity and centripetal acceleration? What is the tension on the string if the rock has a mass of 0.5 kg?
  1. What is the gravitational pull between two 2000kg objects that are 0.1 m apart? Name something that might have a mass of 2000kg
  1. The kinetic energy of a car is 30000J, how fast is it going if the mass is 1400 kg?
  1. How much voltage is at the battery if the resistors each have a value of 3ohms and the current through them is 2 amps?
  1. How much power is used by a 120 V bulb that is pulling 2 amps through it?
  1. A personis in a stationary canoe (person plus canoe and anchor is 150kg). The person throws the 20 kg anchor out the back at 5 m/s. How fast is the canoe and person (combined 130kg) now going? And in which direction?
  1. What is the impulse applied to the floor when a 0.4kg ball hits it at 3m/s and bounces back up at 3 m/s? Is that an elastic collision?
  1. How much torque is the 30 kg weight generating around the pivot point of the see saw? Where should the 55kg weight be placed to balance it out?

2m

  1. A rabbit is about to chase a dog that has a 3 m head start. The dog can go 3 m/s and the rabbit can go 8 m/s. Write the equations of motion for the dog and the rabbit using the rabbits starting point as the origin. At what distance will the rabbit catch the dog and how long will it take?

Back

  1. The coaster starts at the first hill from rest, what is the speed of the roller coaster at A and B? Assume no friction. What is the potential energy at the first hill? m=100kg

B

20m

15m

A

Graph Practice

Answer the following using the above graph

  1. From 0 to 40 s what was the average velocity?
  2. At 20 s what is the instantaneous velocity?
  3. From 0 to 70 s what was the average velocity?
  4. From 70 to 90 s what was the average velocity?
  5. At 80 s what is the instantaneous velocity?
  6. For the whole trip 0 to 100 seconds what was the average velocity?

.

Answer the following using the above graph

  1. From 0 to 30 s what was the average acceleration?
  2. At 20 s what is the instantaneous acceleration?
  3. At 30 s what is the velocity?
  4. From 30 to 40 s what was the average acceleration?
  5. At 45 s what is the instantaneous acceleration?
  1. At 55s what is the instantaneous acceleration?
  1. What is the distance covered from 0-30 s?

Answers to Final Review CP PhysicsFrye

  1. 3150in
  2. 131.2 ft
  3. 4.8E-10C
  4. 8.66x – 5y
  5. 10y
  6. 0, 20, 30, 0, 0, -9.8 x=30t y=20-1/2(9.8)t2 t=2.02s 60m
  7. t=3s x=42.8m
  8. a=-7.29 m/s/s F=8932N x = 58.5m
  9. 10.4 m/s @17°
  10. 250J 1.6m/s
  11. 80J , 98%, 39.2N
  12. 0.15m/s/s
  13. 1.18m/s/s
  14. f=.25Hz v=3.14 m/s a = 4.9 m/s/s F=2.5N
  15. 0.027N
  16. 6.55m/s
  17. 18V
  18. 240W
  19. 0.67
  20. 2.4 Ns
  21. 588Nm 1.1m
  22. t=0.6s x=4.8m
  23. vA = 19.8m/s, vB=9.9m/s

Graphs

  1. 10
  2. 10
  3. 5.7
  4. -10
  5. -10
  6. 0
  7. 0.5
  8. 0.5
  9. 15
  10. 0
  11. -1/2 m/s/s
  12. 0
  13. 225m

Answers to Final Review CP PhysicsFrye

  1. 3150in
  2. 131.2 ft
  3. 4.8E-10C
  4. 8.66x – 5y
  5. 10y
  6. 0, 20, 30, 0, 0, -9.8 x=30t y=20-1/2(9.8)t2 t=2.02s 60m
  7. t=3s x=42.8m
  8. a=-7.29 m/s/s F=8932N x = 58.5m
  9. 10.4 m/s @17°
  10. 250J 1.6m/s
  11. 80J , 98%, 39.2N
  12. 0.15m/s/s
  13. 1.18m/s/s
  14. f=.25Hz v=3.14 m/s a = 4.9 m/s/s F=2.5N
  15. 0.027N
  16. 6.55m/s
  17. 18V
  18. 240W
  19. 0.67
  20. 2.4 Ns
  21. 588Nm 1.1m
  22. t=0.6s x=4.8m
  23. vA = 19.8m/s, vB=9.9m/s

Graphs

  1. 10
  2. 10
  3. 5.7
  4. -10
  5. -10
  6. 0
  7. 0.5
  8. 0.5
  9. 15
  10. 0
  11. -1/2 m/s/s
  12. 0
  13. 225m