Physics Core/AP 1 and 2

Physics Lab

# Physics Lab: Spring Constant

## Goal: To determine the spring constant for a 5" spring.

#### Materials

• One or more 5" springs (available at a hardware store)
• Other equipment as you deem necessary!

#### Procedure

1. Design a lab to determine the spring constant k for a narrow 5-6" spring [if you have the Physics lab kit, use the Hooke's constant spring so that you can compare data with your peers]. You may consult with your fellow students use similar or different methods. Come up with a way to suspend the spring, attach your weights, and measure the displacement x caused by force of the weights. The spring constant k will be F/x.
2. How many trials should you make?
3. What components of the spring force equation can you vary? What should you vary? What are the limits of your variations? [Remember that stretch the spring too far will destroy its springyness and change its constant.]
4. Determine the spring constant using you method for at least two other springs. If possible, collaborate (identify similar springs in your kit and compare your results with your peers).

#### Data Handling

2. Show how plotting data such as force against extension can give you a value for k, the spring constant.

#### Report

1. Describe your materials, equipment, an dprocedures in sufficient detail that your fellow students could repeat your experiment.
2. Report your data. Be sure to indicate the amount of error in your measurements. For example, if you can only measure a mass of 25 gms within 1 grm, your error would be 25 ± 1, or 1/25 = 4%.
3. Present your data in an organized form, preferably in a table, in such a way it is easy to compare results as you repeate trials or vary a specific contributing factor.
4. Show a sample calculation, if you have calculated values.
5. If you did a series of experiments, varying something by increasing or decreasing a factor, try to plot your data (y-axis) as a function of the factor (x-axis).