1C30.16 - Free-Fall Apparatus

Code Number:
1C30.16
Demo Title:
Free-Fall Apparatus
Condition:
Good
Principle:
Measurement of 'g'
Area of Study:
Mechanics
Equipment:
20 Volts DC Power Supply, Electromagnet, Electric Timer, Switch Pad, Close-Up Lenses, Camera, Camera Power Supply, Ball Bearings, Air Track, Timing Gates and Counters, Air Cars, Behr Freefall App., Power Supply (Old Variable Type), Switch, Spark Generator and Spark Tape, Laptop and Interface, Photogate, and Picket Fence. Videotape of Objects Thrown of the Roof of Van Allen Hall.
Procedure:

Hookup is as shown using the appropriate adapters. For ease of measurement the distance between the ball bearing when it is suspended in the electromagnet and the switch pad should be 1 meter. The screws in the switch pad need to be tightened periodically to insure a good electrical contact.

Measurement can also be made by using an inclined Air track and timing the cars through a known distance.

The Behr Freefall App. needs to be carefully leveled to insure that the weight will fall at the proper distance from the wire so that good sparking is achieved.Inserting a switch between the power supply and magnet will make it easier to turn of the magnet and allow the weight to fall.

Another way to quickly do a measurement of "g" is to drop one of the picket fences through a Photogate. Place a foam pad under the Photogate to prevent damage to the picket fence.

The video tape shows a variety of objects being thrown off the roof of Van Allen Hall. The entire 7 story drop is viewed so that you can make measurements if desired. Also, objects are dropped in pairs so that you can see their simultaneous fall.

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