Problem Solving in Physics

1. Conservation of Energy

1.1. Energy is usually conserved. Carefully note what kinds of energy you start and finish with and make them equal to each other.

2. Conservation of Momentum

2.1. Are there any eternal forces?

2.1.1. Yes

2.1.2. No

2.1.2.1. Great! Momentum is conserved, so final momentum=initial momentum!

2.2. Are there any eternal torques?

2.2.1. No

2.2.1.1. Great! Angular momentum is conserved! Initial=final.

2.2.2. Yes

3. Formulas

3.1. Check your formula sheet - are there any formulas that have the variables you need to solve this problem?

4. Trig Identities

4.1. Solving a triangle? Use SOH CAH TOA to find unknown quantities

5. Sum of the Forces

5.1. Remember, the Sum of the Forces F=ma - if there is no acceleration, there is no net force!

5.2. This works for the sum of the torques too. The sum of the torques =I(alpha)