3A40.21 - SHM and Rotational Motion - Pendulum

Set the pendulum up so that it is directly over the center of the turntable.  Place the painted wooden block at the edge of the turntable.  When the needle arm is moved out of its carriage the turntable will start to rotate.  Practice will be needed to be able to start the pendulum in phase with the rotating block on the turntable.  The pinpoint light source is used to create a shadow graph of this on the screen in the lecture room.
Code Number:
3A40.21
Demo Title:
SHM and Rotational Motion - Pendulum
Condition:
Good
Principle:
Comparison of SHM and Rotational Motion
Area of Study:
Acoustics
Equipment:
Turntable app., pendulum app., lazy susan.
Procedure:

Set the pendulum up so that it is directly over the center of the turntable.  Place the painted wooden block at the edge of the turntable.  When the needle arm is moved out of its carriage the turntable will start to rotate.  Practice will be needed to be able to start the pendulum in phase with the rotating block on the turntable.  The pinpoint light source is used to create a shadow graph of this on the screen in the lecture room.

The turn table is placed on top of the lazy susan.  Slight differences in phase due to the slow release of the pendulum can be compensated for by rotating the turn table/lazy susan unit.

References:
  • Greg Jakovidis,  "Demonstrating the Relationship Between Circular and Simple Harmonic Motion",  TPT, Vol. 35, # 2, p. 177, Feb. 1997.
  • Fr. Earl Meyer, " Simple Apparatus for Simple Harmonic Motion", TPT, Vol. 3, # 3, March 1965, p.127.
  • David Kutliroff, "67, Simple Harmonic Motion Is Displayed by a Rotating Turn Table", 101 Classroom Demonstrations and Experiment For Teaching Physics, p. 148.
  • Robert L. Wild, "SHM with Turntable and Pendulum", Low-Cost Physics Demonstrations, # 41, p. 27.
  • Earl Meyer,  "Simple Apparatus for Simple Harmonic Motion",  Apparatus for Teaching Physics, p. 55.                                                    


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