## Momentum and Collisions

Egg Drop
Egg Drop activities are loads of phun. This simulated version allows a learner to explore the variables that result in a safe landing or a fractured or broken egg. The accompanying activity sheet is intended for use with a classroom; its emphasis is on the use of science reasoning skills to understand the physics behind an egg drop activity.

The Cart and The Brick
This activity involves the analysis of a collision between a moving cart and a dropped brick that lands on top of it. Position-time data are used to determine the pre- and post-collision speeds of the cart and the brick. The individual momentum values of the two objects are calculated before and after the collision and analyzed. This Interactive is accompanied by an activity sheet.

Fish Catch
Can the relative mass of two colliding objects be used to quickly predict the post-collision speed of the objects? Learners can use the Fish Catch Interactive to explore this question. The Interactive is accompanied by an activity sheet that guides learners through the process of determining the rule for predicting the post-collision speed from the relative mass of the two objects.

Consider two side-by-side carts on a low-friction track. The carts are equipped with a spring-loaded plunger. When the plunger is activated, the carts push away from each other and are propelled in opposite directions. How does the relative mass of the two carts affect that outcome of the explosion? Does the more massive cart acquire the greater post-explosion velocity? Or is the least massive cart moving faster after the explosion? Or does the mass not make a difference? Explore these questions and more with the Exploding Carts Interactive.
Pick a cart, put it on a track and slam it into a second cart. Change the mass and/or the velocity and repeat the experiment. Put two carts next to each other on the same track with a firecracker between them, Ignite the fuse and watch the carts fly apart when the firecracker explodes. Do all this and more without getting yelled at by your physics teacher or sent to the deans office for possession of incendiary devices. What a blast!