Physics Project Proposal

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Physics Project Proposal

• Feb.,2003
• Topic
• Expected outcome/results
• Experimental work
• Theoretical background
• Schelude
• Problems encountered

2
Choosing a topic

• Related to the physics already learned, or going
  to learn later
• Both theory and experiment involved (or
  craft-work, model-making instead)
• Not too complicated, easily to be understood

3
Choosing a topic example

• Study the period of an interrupted pendulum
• (ref Physics Teacher, 40, p.476)
• Area SHM

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What you expect to find?

• Make use of apparatus to measure physical
  quantities period (T), lengths (L, Ls, h, etc.)
• Describe how T depends on L, or Ls.
• Find the relationship between some quantities,
  say TT(Ls) or T(h).
• See what is deviated from theory.

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What you expect to find?

• Plot graphs, say T vs Ls, or T vs h.
• Compare with well-known results
• Try to explain some observation in the
  experimental result. Also point out the new
  knowledge, if any.

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Experimental work

• A workable design is very important.
• Before conduct the experiment, you should ask
  what apparatus is provided by our physics lab.
• Try to list procedures and predict what result
  you will obtain.
• The lab. work should be as simple, clear as
  possible.

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Experiment example

• Apparatus string, clamp stand, copper bob,
  stop watch
• Procedures the same as we did in practical
  sessions.
• Expected measurement
• (1) period for diff. Ls (w/ h constant)
• (2) period for diff. H (w/ Ls unchanged)

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Experiment setup
The peg
Ls
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Experiment demonstration
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Theoretical background

• Search possible backup from textbook, literature,
  web-sites, etc.
• Sort out those information you can understand and
  easier to be received by your classmates.
• Try, based on your research, formulate a
  theoretical basis for your project.

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Theoretical background

• If you have confidence, try to understand what
  results obtained from your experiment. Then, work
  out your own theory and show/suggest your
  conclusion or any prediction.
• Well, you are a physicist in SWCSSS!

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Theory example

• From the paper, we have,
  T0 period w/o
  the peg.
• A computer calculation is shown.
• As mentioned in textbook, the result is not so
  simple, while q is larger than 30o. Check it!

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Theoretical calculation
T/T0
Ls/L
Result 1 T in simple pendulum formula Result 2
T is corrected to 2nd order for large amplitude
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Comparison w/ theory 1
Result 1 T/T0 in experimental work
Result 2 T/T0 by theory with large amplitude
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Comparison w/ theory 2
Result 1 Measurement of T/T0 with h, in
experimental work Result 2 Calculation of ratio
of T/T0 with h
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Comparison w/ theory 3
A plot of log(2(T/T0)-1) vs log(Ls/L), as shown.
From the graph, Dy0.2, Dx0.4 Slope 0.2/0.4
0.5 Theoretical value of the slope 0.5!
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Schelude
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Problem encountered

• Only traditional apparatus is provided by the
  lab. So, measurement may be not accurate.
• Mathematical basis is not enough to formulate a
  model for large amplitde oscillation.