Restoring Force Investigation                                                      Name:

                                                                                                      Date:

 

            The purpose of this lab is to investigate the restoring force exerted by a spring.  The goal is to have a conceptual and mathematical understanding of this force and how it behaves in an oscillating system.  Students will use spring scales to measure forces exerted by a stretched spring.

 

 

 

 

 


Materials Needed

            Spring force scale (or force probe)

            Spring

            Ruler

 

Classroom Discussion:

Begin by slowly stretching a spring between both hands. Answer the following questions through class discussion:

 

  1. Describe what you feel as you slowly pull the ends of the spring apart?

 

 

 

  1. Does the force you apply to the spring change as you pull the ends further apart?  Make a generalization relating the amount of force applied to the amount of stretch.

 

 

 

  1. What factors might affect the amount of force exerted by the stretched spring?

 

 

 

  1. Design an experimental procedure to quantitatively test how the amount of stretch relates to the amount of restoring force. 

 

 

 

  1. In your experiment, what is the dependent variable? What is the independent variable?

 

 

 

 

 

Investigation:

Carry out the experimental procedure the class developed, investigating the       relationship between the stretch of the spring and the restoring force.  Collect and record results in a careful, organized manner.  Make sure to collect enough data to perform reliable mathematical analysis.

 

 

Analysis:

Graphically analyze your data in order to determine a mathematical interpretation of the data.  Record or print out your results.

 

 

Conclusion:

Write a summary of this investigation.  Be sure to describe your experimental procedure and to express what effect spring stretch has on restoring spring force.

 

 

 

 

 

Restoring Force Homework                                                                                                            Name:

                                                                                                            Date:

 

1)     The diagram below shows a mass attached to a spring undergoing horizontal oscillation about its equilibrium position.  The spring in a) is not stretched.  The mass is displaced in b) and then released.  In c), d), e), f) the mass oscillates.  In each picture, draw a vector showing the force that the spring exerts on the mass.

 

a)        

 

 

 

 


b)        

 

 

 

 


c)        

 

 

 

 


d)        

 

 

 

 


e)        

 

 

 

 


f)         

 

 

 

 

 


2)     Describe the behavior of the force over time in the situation described above.  Be sure to discuss the magnitude and the direction of the force.

 

 

3)     Sketch a graph of the force applied by the spring versus time for two complete oscillations of the mass.