Types of oscillators: simple harmonic, damped and forced.

Procedure for the experiment is as follows:

1.To study the Simple harmonic motion
  • step1: Read the theory

  • step2: Set the damping factor (b) = 0

  • step3: set vo= 0 m/s

  • step4: Drag the ball to maximum starting position say xo= 10.0m and play the animation button.

  • step5: Observe the graph,wait until the animation ends

  • Graph representing S.H.M motion (position graph)

    screenshot1

    Graph representing S.H.M motion (position and velocity graph)

    screenshot2

2.To study Damped oscillatory motion

  • step1: Reset the simulation

  • step2: Set vo= 0 m/sec

  • step3: change the damping factor(b) from 0 to some value take three cases and reset the simulation in each case

    • Case 1:Under-Damping

    • Set the value of b < 2√2 (say b= 0.5)

      Graph representing under-damped oscillatory motion (position graph)

      screenshot3

      Graph representing under-damped oscillatory motion (position and velocity graph)

      screenshot4
    • Case 2: Critical-Damping

    • Set the value of b = 2√2

      Graph representing critical-damped oscillatory motion (position graph)

      screenshot5

      Graph representing critical-damped oscillatory motion (position and velocity graph)

      screenshot6
    • Case 3: Over-Damping

    • Set the value of b > 2√2 (say b= 3)

      Graph representing over-damped oscillatory motion (position graph)

      screenshot7

      Graph representing over-damped oscillatory motion (position and velocity graph)

      screenshot8
  • step4: Drag the ball to maximum starting position say xo= 10.0m and play the animation button.

  • step5: In all the above three cases mentioned observe the graph and wait till animation ends.


3.To study Forced oscillatory motion

  • step1: Reset the simulation again

  • step2: Set the damping coefficient (b) > 2√2

  • step3: Change the value of initial velocity vo= 2m/sec

  • step4: Set value of driven frequency(ω) = 1.41

  • step5: Set some value of driven amplitude Fo which will be the force for oscillation

  • step6: Drag the ball to maximum starting position say xo= 10.0m and play the animation button.

  • step7: Observe the graph till the animation ends

  • Graph representing forced-oscillatory motion (position graph)

    screenshot9

    Graph representing forced-oscillatory motion (position and velocity graph)

    screenshot310

Perform the following experiments

Experiment-1:

Perform experiment to calculate the value of k (spring constant) in the following cases described below.In each case record observations into the table and compute the value of k.Take value of m =1 kg in each case.

  • Case 1: Free oscillator (simple harmonic motion) when b = 0

    1. set different values for xo

    2. keep other parameters = 0

    3. record the value of time in each case

    4. calculate corrosponding angular frequency

    5. then compute k (spring constant) using formula

      shock absorbers

    6. S.no xo (displacement) f (frequency) ω (angular frequency)
      1.
      2.
      3.
      4.
      5.
      6.

        The mean ω: _________

      • Computed value of k:__________


  • Case 2:Under-Damped damped Oscillator when b < 2√2

    1. set different values for xo

    2. set b<2√2 and keep other parameters = 0

    3. record the value of time in each case

    4. calculate corrosponding angular frequency:

      shock absorbers

    5. Value of b used in the experiment:_________


S.no xo (displacement) f (frequency) ω (angular frequency)
1.
2.
3.
4.
5.
6.
  • The mean = ________

  • computed value of k=_____________


  • Case 3: Forced oscillator when b > 2√2

    1. set different values for Fo

    2. set driven frequency ω =1rad/sec,

    3. obtain the value of amplitude by observing graph each time.

    4. obtain the value of ω using the relation:

      shock absorbers

    5. then compute k (spring constant) from the calculated mean value of


    6. S.no Fo (force) A (amplitude) ω (angular frequency)
      1.
      2.
      3.
      4.
      5.
      6.
      • The mean ω = ________

      • computed value of k =_____________