Simple Pendulum Lab – Simulation Based.
Show your solutions for the exercises below, including all the equations you used, all the calculations you performed and at least three relevant screen shots.
Objective: Use concepts of oscillations in the given pendulum and find out its time period.
Material: Use this Phet simulation for Simple Pendulum.
https://phet.colorado.edu/sims/html/pendulum-lab/latest/pendulum-lab_en.html
Procedure: Part I – Find out time period (T) of Pendulum.
- When you click to this website, it will take you to this page.
- Pick “Intro” from this screen. Then you will see this page.
- Test each button on this page to understand their functions.
- Now pick one particular length (L), mass (M) and gravity of Earth, No friction.
- Use stopwatch to record time of oscillation of the pendulum and pick “Slow” motion on the screen before you deviate your pendulum. The screen will look like this.
- Now deviate pendulum on left side by -33 degrees and the screen will show you that angle. See in the screen shot here.
- Count it as zero and also start your stopwatch at this time. Let the pendulum oscillate.
- Count 1 when pendulum reaches to the same position where it started.
- Keep counting for 10 oscillations and record time of 10 oscillations and then stop the stopwatch. See the screen shot here.
- The time shown in the stopwatch is the time for 10 oscillations here and it is t = 0.1705 s.
- Now use this time “t” to calculate Experimental time period “T” using this formula.
Texp = t/10.
- Now calculate theoretical time period of the pendulum using this formula where g = 9,81 m/s^2.
Tth = 2*pi*√(L/g)
- Now find out percent error in between these time periods using this equation.
% error = (Tth-Texp)*100/Tth
Part II – Find out time period (T’) of Pendulum when mass is increased.
- Now repeat all steps from step 6 -13 with a different mass of the pendulum. Try picking up a heavier mass.
- You are changing mass only. Rest of the things will stay same as before i.e., Length, gravity and friction.
- How time period of the pendulum with heavier mass (T’) is different than time period (T) you found in the Part 1?
Part III – Find out time period (T”) of Pendulum when length has increased.
- Now repeat all steps from step 6 -13 with a longer length of the pendulum. Keep mass same as part I.
- You are changing length only. Rest of the things will stay same as before i.e., mass, gravity and friction.
- When you are calculating theoretical time period Tth, use new length of the pendulum there.
- How time period of the pendulum with longer length (T”) is different than time period (T) you found in the Part 1?
Part IV – Find out time period (T’”) of Pendulum when gravity has increased.
- Now repeat all steps from step 6 -13 with same length, mass and friction as before you had in part I but change gravity from Earth to any other place.
- You are testing effect of gravity here. Make sure when you calculate theoretical time period of the pendulum Tth, use your changed gravity.
- How time period of the pendulum with different gravity (T’”) is different than time period (T) you found in the Part 1?
Part V – Find out time period (T’’”) of Pendulum when angle of deflection is changed to lower value of angle.
- Now repeat all steps from step 6 -13 with same length, mass, friction and gravity as you have used in Part I, but change the angle of deflection to any smaller number than -33 degrees, example is 20 degrees.
- You are testing effect of angle that is used to deviate pendulum here.
- How time period of the pendulum with different gravity (T’’”) is different than time period (T) you found in the Part 1?
- Now type a full lab report and show your all results, screen shots, calculations, and discussion and conclusion.
- In discussion and conclusion, show how time period of the pendulum is affected by mass, length, gravity, angle.
© 2022 Dr Dipti Sharma