Duane Merrell

Brigham Young University

Eyring Science Center

N – 143

Provo, UT 84602

801-422-2255

duane_merrell@byu.edu

Multipurpose Pop Bottle Accelerator

Abstract (50-75 words)

This multipurpose Pop Bottle Accelerator will launch straw rockets, pop bottle (20 oz), one liter and two liter rockets. The accelerator will power pop bottle drag racers, (this takes two accelerators). It is prepared to do variable angle launches for studies in projectile motion. It can blast a packaged egg into a wall creating a violent collision. Students can do experiments through out kinematics with this one piece of physics apparatus.

Construction of Apparatus:

Construction of the Pop Bottle Accelerator takes a skilled machinist and a little time. The Pop Bottle Accelerator described here was constructed for me by Wesley H. Lifferth, Brigham Young University Physics Machine Shop. The use of a lathe and milling machine were important but all other materials came from home depot, and Grainger supply type of stores. The issue of too much pressure has been dealt with by using the variable pressure relief valve.

Use of Apparatus:

Using the Pop Bottle Accelerator is quite simple. Push the pop bottle that you want to accelerate onto the o-ring. Secure the bottle in place with the release mechanism, (trigger). Pump air into the bottle, (designed as a rocket, egg blast, drag racer, ECT). Stand back and pull the release and let the acceleration begin. Use water if desired to make a water rocket for higher accelerations, more height, further distance, faster race cars, ECT.

The Pop Bottle Accelerator is one piece of science equipment that can have students doing labs and collecting and analyzing data from many physics concepts.

Projectile Motion:

Study the flight of a projectile by having the students construct rockets that will fly a maximum horizontal distance. Using video analysis software or just stop watches and distance measurements collect the data from the launch. Students control variable such as, mass, aerodynamic design, angle, water in rocket, to build and fly a rocket for maximum horizontal distance.

Newton’s Laws:

During the design of the rocket, mass (Inertia, Newton’s First Law) come into play as the rocket starts to fly consistently. Mass and force (Newton’s Second Law) come into play as the ratio giving acceleration is explored. The amount of water in the bottle comes into play as the correct amount is sought. Action-Reaction (Newton’s Third Law) bottle pushes out water and water pushes on bottle, seems to be better that bottle pushes out air, air pushes on bottle. Data is collected in a Mass vs. Distance Graph, Angle vs. Distance Graph, Water vs. Distance Graph and then using the information from each graph the student’s design a rocket that will fly a maximum horizontal distance. They decide, design, mass, angle, amount of water, pressure is controlled by the teacher.

Momentum:

Impulse momentum can be discussed by attaching an egg on the front of the bottle and accelerating the egg in its package into the wall. Very violent collisions occur but eggs can and do survive. I reward the success of the project based on the mass of the package. The least mass packages receive more points than the massive packages. The ratio of force/mass when it comes to acceleration is apparent in this project also.

Equipment and costs required to construct apparatus:

Item	Source	Part number	Cost
Variable Pressure Relief Valve	Grainger	4TK26	$9.13
Aluminum	Metal Mart		$12.00
Metal Trigger	Metal Mart		$1.00
Handle	Home Depot		$1.50
Bolt & Washer	Home Depot		$1.00
Tire Pump	Home Depot		$8.00
Quick Couples O-ring	Home Depot Home Depot	#12	$1.50 $.50
Total Cost			$34.63