# 1D50.50 - Central Forces - Centripetal Force

Code Number:
1D50.50
Demo Title:
Central Forces - Centripetal Force
Condition:
Good
Principle:
Forces Due To Circular Motion
Area of Study:
Mechanics
Equipment:
Pasco Centripetal Force App., Weight set, Cenco Centripetal Force App., Variable Speed Rotator, Strobe Light.
Procedure:

Hang weights on the pendulum on the Pasco rotator until it hangs straight up and down.  Record that weight and then remove.  Now, rotate the apparatus until the pendulum hangs straight down again and record the rotation rate.  The force applied by the rotation rate is the same as the static force applied by the weights.

Attach the centripetal force app. to the variable speed rotator. Increase the rpm's on the rotator until the mass in the centripetal force app. extends the spring to the end of the app.. Using the strobe light will provide the stop action viewing necessary for this step. Next hang the centripetal force app. from a hook and hang mass onto the app. until you find how much mass it takes to extend the spring the same amount it was extended when the app. was rotating.

The Max-Air plane is a battery power device that can be connected to a tether in the lecture rooms.  LR70 is probably the easiest room to do this in.  Centripetal force data can be obtained when the plane is flying in a circle while connected to a scale or force sensor.  Charge and discharge the batteries in the plane once.  After that, for every second that you charge the plane battery, you will get one second of run time from the plane motor.  Charging for 20 seconds or less seems to work well in LR70.

References:
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