# Physics Problem Solving

1. Draw a diagram of the situation, if possible.
2. Identify the specific question:
1. What physical property is required?
2. What object possesses this property?
3. What are the units for this property?
4. How many significant figures should the answer have?
3. Identify the pertinent information given in the problem.
4. Identify information that is required but must be obtained outside of the problem.
5. Do any necessary unit conversions.
• All of the units in the problem should be compatible with one another and appropriate for the quantities involved.
• e.g. - Meters per second is not compatible with kilometers.  Light years is not appropriate for the depth of a swimming pool.
6. Identify the general physical concepts and laws that are appropriate to the problem.
7. List the appropriate equations.
8. Restate the problem for clarity, if necessary.
9. Solve the equations as necessary
10. Do the necessary substitutions and calculate the result(s).
• If the unit conversions were done correctly in step #5, the result will have the correct units.
• DO NOT carry the units through the calculations.  They will get in the way and cause confusion!
11. State the answer in an appropriate form with reasonable units.  Clearly identify the answer in some visual way.

### The order of these steps should be adjusted whenever it aids the solution. Thomas Fitzpatrick
St Joseph's Preparatory School