Basic Idea:

• Measure the acceleration of a cart on an inclined track.

• 5 

What:	How Many:	Where:
Air Tracks	1	151 Lab (Bewkes 204)
Air Carts	1 – Large, or 1 – Small	Majors Storeroom, shelf B3
Photogates	1	non-Majors Storeroom, glass cabinet
Metersticks & 2-Metersticks	One 1-m Two 2-m	non-Majors Storeroom, shelf AA1

Computers Needed?

• Yes.

• This experiment is setup in the 151 lab (Bewkes 204); it's a lot easier to move students than air tracks!

• Air track setup (connect to the overhead air supply with a hose clamp). Photogate timer is attached near the 2M mark of the track:
  

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• Leveling of air tracks:
  

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• Attaching photogates to airtrack (the base of the photgate sits on top of the I-beam; use rubber bands to hold it in place):
  

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• Set photogates to pulse, 1 ms, and memory On (the red light is on).

• A 5/8" board is placed under one end of the track to give ~0.5° tilt. Use large carts on two tracks, small carts on the other two; class will see if the acceleration is independant of the mass.

• Aircarts should have small metal angle bracket taped on top flush with one end to trip the photogate. Make sure photogates are tripped by this "flag", and not the cart (there is a small hole in the cart that can cause erroneous readings).

• On sunny days, the window shades should be drawn; bright sunlight will affect photgate performance.

• Be sure the air tracks are as clean as possible - use acetone if necessary. Also, check the under surface of the air carts for dents and scratchs; use a small file to smooth.