Physics orders the phenomenon in our universe by examining qualitative or mathematical relationships that are apparent in them.. In fact it could be stated that physics is applied mathematics. "To do and learn physics", is the answer to the question heard in math classes around the country, "Why do we have to learn this stuff?"

To that end, problem solving is an essential element of any physics class. A strong mathematics background, especially in the areas of algebra and trigonometry, is the best preparation you can have before beginning a course in physics.

When solving problems in physics, whether on tests, quizzes, lab reports, or assignments, there is a certain format that you will be required to follow. This format organizes your work and gives insight as to what physics concepts you utilized in your attempt to solve the problem. That is, this format will determine if your error was simply a mathematical error or if the physics concepts used to solve the problem was wrong. Since this is not a math class this format is as important as whether or not you achieved the correct answer; therefore you will be graded on the format as well as whether or not the answer is correct.

1. Keep your work neat and orderly.
2. Problems must be done in pencil or black ink; the instructor will NOT accept other colors.
3. Distinguish your final answer by neatly circling, boxing, or highlighting it.
4. You may use calculators at any time to solve problems unless otherwise instructed.

You should obtain a scientific calculator that has trig functions (sine, cosine, & tangent), exponents and scientific notation, and logarithms. A general rule is the cheaper the calculator; the easier it is to operate.
The instructor will not provide calculators at any time. Sharing a calculator with another classmate will NOT be allowed during tests and quizzes, although it is permissible at other times.

 

Below is a sample physics problem solved using the format required in this class. Each step in the format is discussed as it introduced. Generally each step earns one point toward the total points that will be awarded for the problem.

The current world record for the men's 100 m dash is 9.79 s set by Maurice Greene of the United States in 1999. Coach King, the track coach at Vandebilt has set this mark as a goal for this year's team. The fastest man on Vandebilt's track team can run at an average velocity of 9.5 m/s for 100 m. Is this good enough for the new world record?

1. Set up:

In the setup you are to list all the given numerical data and any unknown quantities that will be needed to solve the problem. The quantities should be listed by their symbols and should also include the appropriate units. If the same type of quantity appears more than once in a problem use subscripts to distinguish them. To view a list of physics quantities, units, and their symbols click here.

Any acceptable units for a quantity may be used when solving problems; however, remember that metric units (SI)are the standard units for physics. If you are unsure which units to use, then it is best to use the fundamental metric units in the MKS system. The units for similar quantities must be the same before you proceed. Any units that need to be converted should be done in the set up with both the old and new units listed.     For help with unit conversions click here.

An optional part of the set up is to draw a sketch or diagram that represents the given problem. Often this visual aid provides valuable clues to help you solve the problem. There will be certain problems where a diagram is mandatory. You will be instructed as to their specific use at that time.

Sample problem:

d = 100 m
v = 9.5 m/s
t = ?


t_WR = 9.79 s

**NOTE: 9.79 s is listed, but will not be used in your calculations. It is given for comparison purposes only to determine if a new world record will be achieved.

2. Formula:

Next you are to list the formula that you have chosen to use to solve the problem. This formula must be written in its traditional form with only symbols (Do not place any given numerical data in the formula at this time). The formula represents the physics concept that you have chosen to solve the problem. After the original formula is written down you may then solve the formula for the unknown quantity.

To view a list of some common physics formulas click here.

Sample problem:

v = d / t
t = d / v

NOTE: The most common form of the equation is v = d / t, so it is listed first. However, since time ("t") is the unknown quantity, the equation is then solved for "t".

3. First Substitution:

Next substitute into the equation all given numerical data including their proper units. If you fail to include the units you will not be given credit for this step.

If everything has been done correctly up to this point, then the problem has been solved as for as the physics concepts involved. From this point forward you are simply solving a mathematics problems; however, be careful, most mistakes students make on physics problems are mathematical in nature.

Sample problem:

t = 100 m / 9.5 m/s

4. Correct Answer:
5. Correct Units:

Write the correct answer with the proper units. It is not necessary to show any of the mathematical steps between the first substitution and the correct answer. You are not being graded on your mathematical skills, just your knowledge of the physics concepts involved.

Sample Problem:

t = 10.5 s

6. Answer the question:

The current world record for the men's 100 m dash is 9.79 s set by Maurice Greene of the United States in 1999. Coach King, the track coach at Vandebilt has set this mark as a goal for this year's team. The fastest man on Vandebilt's track team can run at an average velocity of 9.5 m/s for 100 m. Is this good enough for the new world record?

No, Coach King should not expect a new world record this year.