Oct. 10 – Newton's 3rd Law

Here's quick review and demo of Newton's Second Law:

Next we talked about Newton's 3rd Law.  I did a demo with a rolling chair.  Here are the notes:

Newton's 3rd law may be easy to write down, but it's can be tricky to understand.  Here are more videos that demonstrate the law:

How do water jetpacks work?  Heres'a diagram:

The jetpack forces water down, the reaction force is the water pushing the person up.  If the upwards force is greater than gravity, the person will accelerate upwards.

Here are more examples of Newton's 3rd Law:

Every time you walk, you are using Newton's 3rd Law!  You push the ground backwards and the ground pushes you forwards!

Homework

• Follow the unit plan and do the homework for day 4.

Here are some solutions for day 3 homework: