Question | Answer |
Inertia in motion is called ______. | Momentum |
Write the equation for momentum. | p = mass x velocity |
In the momentum equation, what is the relationship between momentum and velocity? | They are directly related |
What is acceleration? | A change in velocity |
Name three ways velocity can change? | speeding up, slowing down, or changing direction |
What is momentum if there is no change in velocity? | Zero |
_________causes acceleration. | Force |
Velocity is speed and direction. True or False. | True |
A car is going 2 m/s north. Is this speed or velocity? Why? | It is velocity because we have both speed and direction |
Identify the following measurements as speed, velocity, or momentum:
a. 88 km/h b. 10 m/s straight up
c. 18 kg m/s down d. 19 m/s west | a. speed b. velocity
c. momentum
d. velocity |
Calculate the momentum of a 6.00 kg bowling ball moving at 10.0 m/s down the alley. | p = 6.00 kg x 10.0 m/s
= 60 kg m/s down the alley |
Calculate the momentum of a 75 kg speed skater moving forward at 16 m/s. | p = 75 kg x 16 m/s
= 1200 kg m/s moving forward |
Calculate the momentum of a 1.35 kg ostrich running north at 16.2 m/s. | p = 1.35 kg x 16.2 m/s
= 21.9 kg m/s running north |
Describe the measurements necessary to find the average speed of a moving train. | The distance the train traveled and the time it took to travel that distance must be measured. |
Explain why knowing the velocity of an airplane is more important to a traveler than knowing only the airplane's speed. | Velocity gives the direction the plane is heading. |
_______and _______are important in changing momentum. | Force and time |
What is impulse? | Impulse is force times time |
What is the unit for impulse? | N/s |
An impulse always involves two variables. Name them. | Impact force and impact time |
Why should a golfer swing as hard as possible and follow through the swing? | By doing so, he is creating the greatest force possible for as long as possible which results in a greater impulse and greater momentum. |
Determine the units of a caterpillar's speed if you measure the distance the caterpillar travels in centimeters and the time it takes to travel this distance in minutes. | cm/minute |
Describe why your velocity changes when you ride a Ferris wheel even if the wheel turns at a constant speed. | As the Ferris wheel turns, you are moving in a different direction at each instant of time. Since the direction changes, the velocity changes. |
Describe the motion of a ball in a typical sport. Identify times when the ball moves with a constant velocity and times when its velocity changes. | If a ball moves in a straight line at a constant speed, the velocity is constant. If the ball changes direction or speed, the velocity changes. |
What is the velocity in meters per second of a sailboat that travels 149 m away from the shore in 16.8 s? | velocity = d / t
= 149 m / 16.8 s
= 8.87 m/s away from shore |