30 terms

Momentum and Impulse
4.1 I can list the factors that affect momentum and recall correct units for measuring it.
4.2 I can explain why momentum is a vector
4.3 I can manipulate the p=mv equation to solve for any variable
4.4 I can define impulse and its list of units of measurement
4.5 I can manipulate the FΔt=Impulse equation to solve for any variable.
4.6 I can identify that the impulse must equal the change in momentum
4.7 I can manipulate the FΔt=mΔv equation to solve for any variable
4.8 I c…

What is one way to define momentum

the quantity of a mass in motion

What has more momentum: a Volkswagen Beetle going 55 mph or a fully-loaded Mac dump truck going 55 mph?

The Mac dump truck has more momentum because of its larger mass

(T/F?) An object that is stationary has momentum

False

(T/F?) An object that is more massive than another object will always have more momentum?

False, the less massive object may just be traveling much faster than the more massive object

What factor(s) affect the amount of momentum that an object has?

Mass and Velocity

Momentum is a vector because?

velocity has direction

(T/F?) Mass is a vector.

False, mass is a scalar quantity.

A 5 kg bowling ball travels down the lane at 3 m/s. What is its momentum?

15kg m/s

A 40 kg student runs at 5 m/s to the right. Her momentum is?

200kg m/s

A 50 kg student runs at 4 m/s to the left. His momentum is?

-200kg m/s

A 100 kg student has 200kg m/s of momenta, what velocity is he traveling at?

2m/s

A car has 20,000kg m/s of momenta and is traveling at 10m/s, what is its mass?

2,000kg

The product of Force times Time is equal to?

the impulse acting on the object

Which has a greater impulse: Object #1 that has a 1000 N force act for 15 seconds or the object #2 that has a 100 N force act for 40 seconds?

Object #1

(T/F?) All impulses are the same

False, impulse is the result of Force AND the time in which the force acts, so they are not always the same at all

A force of 25 N acts on a ball for .2 seconds. What impulse does the ball receive?

5 N s

A 100 N force acts on the ball for .1 seconds. What impulse does the ball receive?

10 N s

A 10 N force acts for 1/4 of a minute. What impulse does the object receive?

150 N s

A ball receives an impulse of 50 N s when pushed with a 5 N force. How long did the force push the ball?

10 seconds

Explain: An object that receives the greatest Impulse...

Receives the greatest Change in Momentum

A 1000 kg car receives an impulse of -5N s. What is its change in momentum?

-5 kg m/s

A 10 N force pushes a 500g box for .5 seconds. What is the change in velocity of the box?

10 m/s

A 35 N force pushes an object for .2 seconds from rest to 2m/s. What is the mass of the object?

3.5 kg

How much force is needed to speed up a 90 kg preson from 2 m/s to 8 m/s in 1/2 a second?

1080 N

Which of the following increases the time of a collision involving car accidents, windshield, brick wall? (Curumple zone, seat belt, air bag, or anti-lock breaks)

Crumple zone, seat belt and airbag

(T/F?) Momentum is ALWAYS conserved?

True

Momentum BEFORE a collision is (blank) to the momentum AFTER the collision.

EQUAL

If the momentum of a car is 5000 kg m/s before a collision with a stationary car during a perfectly elastic collision that leaves the first car motionless, then the total momentum after the collision with the second car is?

5000kg m/s

Before a collision, Car #1 with a momentum of 22kg m/s hits Car #2 that has a momentum of 4kg m/s. After the collision, Car#1 has a momentum of 18kg m/s. What is the momentum of Car #2

8kg m/s

Car A ( mass of 1000kg) is stopped at a stoplight before it is collided with Car B (mass of 2000kg) that is traveling at 4m/s just before the collision. After the collision, Car A is traveling at 1m/s, what is the velocity of Car B AFTER the collision?

3.5m/s in the direction that Car B was traveling