## Due 3:30 pm, Tuesday, October 6th

Physics 105, Fall Term, 2009

Did you complete the reading assignment?

Yes
No

## KEY CONCEPTS:

1) Momentum is the product of an object's mass and velocity.

2) Impulse is the change in momentum of an object when a force is applied to it over a given time.

3) Momentum and impulse have the same units, but momentum is something an object has, whereas impulse is something done to an object.

There is not a lot a whole lot of applications for momentum until you start using the Law of Conservation of Momentum and collisions, which is for next time. Here is a slightly, culturally insensitive video that helps explain the difference between momentum and impulse and which one is most important for trying to break stuff: http://www.youtube.com/watch?v=rvHUHTcaxQA

The video explains impulse as how fast momentum is transferred. Is this a correct definition? Why or why not?

The momentum of the guy's fist in the video is what is important to watch. Does the mass of his fist change?

Yes
No

When a board is broken easily, does the velocity of his fist change a lot?

Yes
No

When breaking stuff with you fist, you want to have:

High initial momentum, high final momentum
High initial momentum, low final momentum
Low initial momentum, high final momentum
Low initial momentum, low final momentum

A greater impulse is is when a force is applied over a longer period of time. When breaking stuff, do you want a large or small impulse?

Large impulse
Small impulse

FEEDBACK

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Was there anything that you didn't understand in the reading assignment?  What was confusing to you?