Problem Solving

Problem solving is fundamental to any physics course. It is important in of itself but it also makes you think about the ideas you are working with and causes you to understand them better. It is the difference between knowing the definition of a term and true comprehension.

Problem solving often requires creativity-each problem is different. Here is a general outline of tips to tackle problems. Before you start, you need to know the terminology and principles and laws that apply. Reviewing your notes or the textbook may be of help.

1. Read written problems carefully. A common error is to leave out a word or two when reading which can completely change the sense of a problem.

2. Draw an accurate picture or diagram of the situation and include the information you are given in the problem. This is the most commonly overlooked and most important step. Use arrows to represent vectors and label each vector with appropriate symbols. Use a separate diagram for different types of vectors. A diagram of force vectors is called a free-body diagram.

3. Choose a convenient x-y coordinate system. Choose one that makes calculations easier. Keep track of which direction is positive and negative. Vectors can be resolved into components along these axes.

4. Determine what are the unknowns-that is, what are you trying to find?

5. Decide what you need in order to find the unknowns. It may help to see if there are one or more relationships (equations) that relate the unknowns to the knowns. Be sure the relationship is applicable in a specific case. (It is dangerous for this reason to thumb through a chapter looking for an equation that will work.) It is important to know the limitations of each relationship.

6. Try to solve the problem roughly in your head to catch calculation errors later.

7. Solve the Problem. Keep track of units for they can serve as a check.

8. Consider if your answer is reasonable. It may help to check the units. Finally, round your answer to the correct precision (significant figures).

Having troubles and getting frustrated are part of learning. Talk to a friend or Mr. Klaassen if you need some help. Go to Mr. Klaassen right at 3:05 or fit with your work showing how far you can get in the above steps. You can then discuss the next step in solving the problem.

Remember, the process of struggling with a problem is important to gaining a deeper understanding of the concepts.