Data Sheet

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69. Newton’s First Law of Motion
Build the circuit as shown on the left and you
will light up the heart and star LED. Turn the
hand crank generator (94 & 99) and you
will see the two LEDs become brighter. The
faster you turn, the brighter they will be. If
you turn on the switch (62), the LEDs will turn
off and the lamp (76) will be turned on. Now
you can turn the hand crank generator (94
& 99) and the heart and star LEDs will be
turned on again.
Now try removing the hand crank (94) from
the generator (99). Notice that unlike in
project 67, the shaft on the generator (99)
does not spin. Newton’s rst law of motion
states: An object either remains at rest or
continues to move at a constant velocity,
unless acted upon by a force. Due to the
higher resistance in this circuit compared to
project 67 (two LEDs and a lamp here vs.
one LED and a lamp in project 67), current
through the generator (99) is not quite
enough to create a force inside the generator
(99) to spin the shaft, and thus the shaft
remains at rest.
2nd level