A Problem Solving Framework Based on the work of Heller & Heller University of Minnesota

The traditional “GUESS” method Givens - Identify the “given” information Unknown - Identify what is wanted Equation - Select equation for solution Solution - Solve equation for unknown Survey - Make certain solution is realistic

Physics Problem-Solving Strategy A better metacognitive approach to solving problems Provides students with a more structured approach to solving problems, especially early on in the semester 5 steps: Focus on the problem Describe the physics Plan the solution Execute solution plan Evaluate the solution

Focus on the Problem

Describe the Physics

Plan a Solution

Execute the Plan

Evaluate the Solution

Using the Competent Problem Solver Answer Sheet: Example 1 An airplane lands on a runway at 175mph. The plane uniformly slows to a stop over a distance of 4049ft. What is the average acceleration in meters/second squared? How many g’s does this represent?

Using the Competent Problem Solver Answer Sheet: Example 2 A car’s initial mass and velocity are m and v respectively. A truck’s mass and velocity are M and -V respectively. Assuming a head-on collision where they stick together, what is the speed of the vehicles immediately after the collision? The truck is twice the mass of the car; the speed of the car is one-half that of the truck.

Using the Competent Problem Solver Answer Sheet: Example 3 A toy rocket leaves the surface of the Earth with an acceleration of 35m/s2. After 1.3s, the rocket engine expires. Assuming no wind resistance as it coasts upward, how high does the rocket go?