retired physics curriculum: momentum

I define impulse and then do this lab so the kids can start to see why impulse may be important.

Then I formally define momentum and show impulse = change in momentum, and then they ccan do these problems.

Looking at three type of 1 dimensional interactions: an explosioon, a completely inelastic collision and an elastic collision. Those terms get defined as a result of this lab, and conservation of momentum is then introduced.

Elastic Collisions 1D Derivation

I like to do this derivation in class as there are some useful math tricks in making it much easier.

Elastic Collisions Questions

KEY

These are questions that go with the equations derived in the previous handout.

Lab 9-3 (2D Momentum)

VIDEO

Video analysis of a 2 balls colliding. The yellow ball has a mass of 0.118 kg and the purple ball is 0.159 kg. The floor tiles are 30.5 cm on a side.

Notes - vectors & collisions

2 D collisions in particular can be difficult for people, so it really helps to show what is going on.

Momentum Vector Problems

Just some extra 2D collision problems. Haven't handed this out in a while.

Here are the practice tests and the separate equation sheet.

Physics (algebra)

In this class, we followed Hewitts "Conceptual Physics" and did momentum after Newton's Laws. We tended to save Newton's Third Law for this unit. We did not do any two dimentional analysis in this class, and we did not talk about impulse as the area under a force time graph. Some of the other teachers wrote up some nice sets of problems and online activities, but I don't feel comfortable posting things I did not write.

Lab 7-1 (N3L)

I came up with this my last year teaching the CP class. Unfortunately, I don't remember how well it worked. (I always tried the labs I came up with on my own first, but sometimes what worked well for me didn't translate too well to the kids.) The attempt is to measure the accelerations of two carts using two motion detectors - but the exlosions and collisions can potentially be too quick to get reasonable numbers.

Newton's 3rd Law

KEY

I would often use this is a way for the kids to take notes while I lectured and did demos.

Momentum Concepts

KEY

Just some basic notes and calculations of momentum to get the kids a little comfortable with the units and the formula.

Impulse Problems

KEY

These problems only look at impulse and change in momentum. We use to do this along with the Egg Drop Challenge, posted below after some notes.

The next three labs all had a set of problems at the end that mirrored the lab, so there are answer keys here for the problem parts. The Physics Classroom has a nice little simulation called "Collision Cart Interactive" that allows an easy online version of all these labs.

Lab 7-3 (Inelastic Collisions)

KEY

Two carts colliding with velcro so that they stick together after the collision.

Lab 7-4 (Elastic Collisions)

KEY

Two carts colliding with the magnets. Be careful with the lab - if the carts are pushed too hard, they will still physically crash into each other (and you will be able to hear it) and then the collision is NOT elastic.

Momentum Problems

KEY

These are problems dealing with objects pushing apart or with objects colliding and sticking together.

I had a couple sets of notes I had written out. I don't remember why I did not write up notes for all of it.

Egg Drop Challenge

We used to start the unit with this little challenge, and used it as introduction to impulse and change in momentum. Not many kids were able to make something that survived, and I always tried to tell the kids that I actually wanted them to have to write something up, but if they got lucky then they wouldn't have to. I always felt a little guilty about all the eggs and straws used up.

Retired Physics Curriculum: Linear Momentum

AP Physics (calculus)

Physics (algebra)

page last updated 10/26/23 by david mcclung, copyright 2023, all rights reserved.