Lab Exercise

Hooke’s Law

Hooke’s law simply states that the force exerted by a spring is proportional to how much you stretch or compress it. That is, the more you stretch it, the more total force it outputs. The more you compress it, the more total force it outputs.

Why use springs?

Springs are an excellent example of potential energy! As you apply force and move the end of the spring, you are doing work (because you are applying a force across some distance). That work places energy into the spring due to the position of the end of the spring. We are not going to worry too much about the math or equations behind this as we are just going to observe how energy and a spring might interact.

1. Open the simulation and select the “Intro” tab.
2. Turn on the three vectors: Applied Force, Spring Force, and Displacement.
   • Optionally turn on the equilibrium position marker, it will remain at the base of the displacement arrow, making it unnecessary.
3. Click on the red/black grabber and pull the spring some distance, but not all the way, to the right.
   • Question 1: What is the applied force from the grabber pulling on the spring?
   • Question 2: What is the force pair of the applied force from the grabber onto the spring?
     • How strong is this force?
     • What direction is it in?
4. Repeat the above process but pushing the spring some distance to the left.
   • Question 3: What is the main difference? How does the spring force relate to the applied force?
5. Try changing the slider for the “Spring Constant.”
   • Slide it around a whole bunch and observe how the simulation changes.
   • Question 4: How does the image of the spring change with the spring constant setting?
   • Question 5: How does the position of the end of the spring change with the spring constant setting?
   • Question 6: What are the units of the spring constant? What does this value represent?
6. Select the “Systems” tab.
7. Repeat steps 2-4 from above, selecting “components” within the spring force option.
   • Question 7: What’s different this time?
   • Question 8: If you turn on values, are either of the spring forces the correct strength to make a force pair with the applied force?
     • This is asking, since force pairs are always two forces that are equal and opposite and acting on opposing objects, do you see a singular force pair here?
   • Question 9: What is the force pair with the applied force then? (Note: it is NOT displayed in the simulation)
     • This question is asking you to describe the force, where is it, who/what is doing it, etc.
     • If you’re stuck, consider how the experiment would go without the plate that connects the springs.
8. Select the “Energy” tab.
9. Grab the end of the spring and move it a bit to the right.
   • This can be done either by clicking and dragging the red grabber thing or by sliding the green “displacement” slider at the bottom.
   • Question 10: What do you notice about the potential energy bar graph as you continue to pull the spring to the right? What does potential energy seem to depend on?
10. Now, leave the spring position alone and play around with the spring constant setting.
    • Question 11: How does the spring constant affect the potential energy graph?
11. Reset via the yellow reset button.
12. Now push the spring a bit to the left.
    • Question 12: What do you notice about the potential energy bar graph as you continue to push the spring to the left? Does the potential energy continue to change once you let go and the spring sits still?
13. Select the “Energy Plot” option in the upper right corner.
    • Question 13: Describe the graph of energy vs position. What can you learn from this graph? How do you know that spring energy is a potential energy?
14. Now switch to the “Force Plot” option and check the box next to “Energy.”
15. Slide the spring around a bit.
    • Question 14: What do you notice on this graph as you move the spring? Please describe it in detail.
    • Question 15: Why is the area under the force line equal to the potential energy of the spring?
      • Think about the definition of work (W=Fd)… If the force of the spring increases as you stretch it, then the work being done increases as well…
        • When using constant force over distance this is a single computation of force times distance.
          • This is equivalent to calculating the area of a rectangle: base x height
        • When the force changes over the distance you have to re-multiply force times distance for each tiny step. This means that the work done by each step is a little bit more than the previous step.
          • As each step needs more force the shape we are describing in terms of energy calculation is a triangle! The first step requires very little force, the next step requires a bit more and so on.
          • Is there a triangle that describes work in the graph?

Struggling with your essay and deadlines?

Get this or a similar paper done in as fast as 4 hours, 24/7.

NB: We do not sell prewritten papers. All essays are written from scratch according to specific needs and instructions

✔Secure Service ✔ Plagiarism Free ✔On-time Delivery

WRITE MY PAPER