THE HOOKES!

Objectives: 

1. Describe the relationship between the restoring forces exerted by elastic materials that have been deformed and the amount of deformation that has occurred.

2. Watch both videos on Hooke's Law to explain and describe the mathematical relationship that describes ideal elastic behavior: F=-kx. 

Pre-Lab Discussion:

In this lab, we investigated Hooke's Law, a law in which describes the elastic behavior of objects in terms of the formula F=-kx. The two following videos helped us understand this concept and perform our lab: 

https://www.khanacademy.org/science/physics/work-and-energy/hookes-law/v/intro-to-springs-and-hooke-s-law

http://youtu.be/YFD3ARI1-lw

Materials:

- one large spring

- one small spring

- one rubber band

- one meter stick

- force probe

- LabQuest

- iPad

         

         

                                      

Procedure:

1. Connect force probe to LabQuest

2. Connect rubber band to hook on force probe 

3. Zero the lab quest

4. Deform the rubber band to lengths of 10, 20, 30, 40, and 50 cm

5. Repeat these steps for the smaller spring 

6. Repeat these steps for the larger spring. 

7. Collect the Force and Graph Data 

Graphs on Force:

                                                            rubber band

Data Tables:

Avg K:

Spring 1: -6.825

Spring 2: -0.368

Rubber band: -0.293

Errors:

Errors in this lab may occur in the measurement of displacement. In addition, having different lab members stretch the spring/rubber band may affect the measurement of the force (N). The graphs from the lab quest are also plotted using approximate forces due to misreading the force probe. 

One factor we also may have overlooked is the actual displacement. We displaced the objects from centimeters/meters and did not take in to the account the original placement of the object at zero every time, affecting the displacement.  

Hooke's Law Application: 

As states before, Hooke's law is a principle of physics that states the proportionality of the force need to stretch an object a certain distance. This can be further explained in the following image:

The application of Hooke's Law is F=-kx, k=-F/x, x=-F/k. In real life, objects have a certain 

elasticity - the ability of an object to return to its normal shape after being stretched or compressed

and 

stiffness - resistance to deformation 

meaning they can only be stretched so far without being deformed. We see this principles of springs throughout our day, such as the spring in pens, rubber bands, clothes, hair elastics, etc.