Impulse and Momentum Study Notes

Variable Symbols

• Az: Displacement

• v: Velocity

• a: Acceleration

• t: Time

Quiz - Impulse and Momentum - 2

Instructions

• Name:

Part 1 - Multiple Choice (1 point each)

Question 1

• An object with mass has a positive velocity and moves at ground level. Which of the following statements is true?

  • a. The object has a positive momentum.

  • b. The object has a positive kinetic energy.

  • c. The object has no gravitational potential energy.

  • d. All of the above.

Question 2

• In order to have momentum, an object must have which of the following?

  • a. Velocity

  • b. Position above the ground

  • c. A potential gravitational energy

  • d. Force acting on it all the time

Question 3

• A skateboard moves along a frictionless level road at a constant speed. Bart suddenly jumps on the skateboard, increasing the mass. What happens to the velocity of the skateboard?

  • a. It increases

  • b. It remains the same

  • c. It decreases

  • d. It stops immediately

Question 4

• A construction worker initially resting on an icy pond throws a hammer. After being thrown, the hammer moves in one direction while the construction worker moves off in the other direction. Which of the following correctly describes this occurrence?

  • a. The construction worker and the hammer will have equal amounts of kinetic energy.

  • b. The hammer will have a greater magnitude of momentum.

  • c. The construction worker will have a greater magnitude of momentum.

  • d. They both will have equal and opposite amounts of momentum.

Example Data for Questions 5-7

• A 3 kg ball is dropped onto a concrete floor. Just before striking the floor, the ball has a velocity of 7 m/s and when it rebounds, its speed is 4 m/s. Consider down to be negative. Units omitted on purpose.

Question 5

• What is the momentum of the object just before it hits the ground?

  • a. -12

  • b. -28

  • c. -21

  • d. -84

  • Formula: $P = mv$

Question 6

• What is the momentum of the object just after it hits the ground?

  • a. 12

  • b. 28

  • c. 21

  • d. 84

Question 7

• What is the impulse acting on the ball?

  • a. 33

  • b. 12

  • c. -33

  • d. -12

Additional Variables

• E: Total mechanical energy ($E = KE + PE$)

• KE: Kinetic energy

• PE: Potential energy

• J: Impulse

• A: Wavelength

• f: Frequency

• T: Period

• n: Index of refraction

• c: Speed of light in a vacuum

• θ: Angle

• θc: Critical angle

• R: Resistance

• V: Volume

Quiz - Impulse and Momentum - Continued

Question 8

• When the velocity of a moving object is quadrupled, which of the following is also quadrupled?

  • a. Kinetic energy

  • b. Acceleration

  • c. Momentum

  • d. Potential energy

Question 9

• Which of the following has the largest momentum relative to the Earth's surface?

  • a. A dog running down the street

  • b. The Eiffel Tower

  • c. A pickup truck speeding along a highway

  • d. A tightrope walker crossing Niagara Falls

Question 10

• Which of the following has the largest inertia relative to the Earth's surface?

  • a. A dog running down the street

  • b. The Eiffel Tower

  • c. A pickup truck speeding along a highway

  • d. A tightrope walker crossing Niagara Falls

Question 11

• A 4 kg ball has a momentum of 12 kg m/s. What is the ball's speed?

  • a. 3 m/s

  • b. 4 m/s

  • c. 48 m/s

  • d. 12 m/s

Question 12

• A small car and a large truck collide head-on. Which one has the largest momentum change?

  • a. The car

  • b. The truck

  • c. They both have the same momentum change

  • d. Can't tell without knowing the final velocities

Question 13

• Which of the following represents the units for momentum?

  • a. $kg imes m$

  • b. $kg imes m²$

  • c. $kg imes m^2$

  • d. $kgm^2/s</p></li></ul></li></ul><h5>Question 14</h5><ul><li><p>Which of the following represents the units for impulse?</p><ul><li><p>a.$ kg imes m $</p></li><li><p>b.$ kg imes m² $</p></li><li><p>c.$ kg imes m^2 $</p></li><li><p>d.$ kg/m $$