Reading Quiz 11 Key

Reading Quiz 11 Key

Due 3:30 pm, Tuesday, October 6th

Physics 105, Fall Term, 2009

Reading: Chapters 6.1 & 6.2

Did you complete the reading assignment?



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:

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?


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


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


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

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