Low Cost Category

2002 AAPT Apparatus Competition, Boise State University

Name: John Makous

Address: 5800 Sardis Road

Charlotte, NC 28270

Phone: (704) 887-7009

Fax: (704) 887-7042

E-mail: jmakous@providenceday.org or jmakous@msn.com

Apparatus Title: Low Cost Collision Carts

Abstract (40-50 words)

A pair of rolling collision carts for demonstrating conservation of momentum and energy will be displayed. This apparatus can be utilized on any table top and does not require an air track. A pair of carts can be constructed for $30.

Equipment required to construct apparatus:

Item	Source	Part number	Cost
General Purpose Cart x 2	Cynmar Corporation	095-18531	$13.95 x 2
Hacksaw blade 1” corner brace x 2 ½” bolt x 2 wing nut x 2 Magnet (optional) Set of masses (optional)	Hardware store Hardware store Hardware store Hardware store On hand On hand		$1.00 $0.21 x 2 $0.10 x 2 $0.21 x 2 ------ ------
		Total Cost:	$29.94

Description:

The apparatus consists of two general purpose carts, each with a 1” corner brace bolted to one end. A 12” hacksaw blade bent in an inverted U shape is mounted on the corner brace of one of the carts, as shown in the diagram. Collisions between the carts will be somewhat elastic, and the transfer of momentum and energy can be demonstrated easily and visually. By adding mass to one of the carts, the mass ratio of the carts can be changed to demonstrate various collisions. Each cart in this apparatus has a mass of approximately 0.50 kg. This apparatus can be used for demonstration purposes or for a laboratory investigation by the students. Inelastic collisions can be demonstrated by replacing the hacksaw blade with a magnet on the corner brace of the one cart, and turning the other cart around so that when the carts collide, the magnet sticks to its corner brace.

Sketch (computer generated if possible):