Handbook of High Speed Photography - IET Labs, Inc.

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Sliding pucks containing cylindrical mognels oriented for mutual repulsion are used to
illustrate the conservation of energy in elastic collisions. Photograph al lop shows the
reduction of speed and kinetic energy as one puck approaches the other, and analysis
shows that this energy is stored in the magnetic field of the pucks. Photograph below
shows the 'explosion' which occurs when the two pucks, originally held closely together
by a string, are allowed lo separate by burning of the string, Quantitative data
obtained from analysis of the first photograph enabled a prediction to be made of
the finol kinetic energy produced by the experiment shown in the second photograph.
Flashes here were at 0.1-second intervals. Used in the PSSC film Elastic Collisions and
Stored Energy.
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