Car With Parallel Circuit (3 Wheels)

This car can travel at a decent pace across flat surfaces, and is a good lesson on how to set up a parallel circuit.

You will need:

- 1 roll of duct tape

- 1 1/2 inch thick piece of plywood around 1ft by 1ft.

- 3 bottle caps (plastic, about 2in diameter)

- 2 batteries (AA)

- 1 small motor with one flat edge

- About 1ft of insulated wire

- 2 screws

- 1 skewer

- 1 straw

(List does not include tools)

Use a ruler and straight edge to create a rectangular 3 by 6 inch section. Trace it, then secure it, and finally cut it, being sure to keep the cut as straight as possible. If the cut is not straight, use a sander to remove excess if possible, although if you do not have access to one, this step is more concerning aesthetics than functionality, except in extreme cases.

Use your roll of duct tape to attach the two batteries to your piece of wood. Do not cover the ends of the batteries.

Cut two pieces off your wire, each about 2in long, and attach one to the positive and positive ends, and the other to the negative and negative.

NOTE: Do not take any other steps that may be shown in picture, this picture also included the motor, and an experimental piece on which to put the motor.

Back to the wood cutter! Using the same technique as before, outline a 1 by 3in section of the plywood and cut it out. Attach this section on the top of the plywood board, about 1 inch in. Drill in the two screws as shown above.

Cut off a section of the straw, approximately 3in long. Attach this with your duct tape to the underside of the car, opposite of the motor. Poke holes through the centers of the three bottle caps. Stick the skewer through the straw, and then slide the one bottle cap onto each end of the skewer. (We will use the third in the next step)

Slide the third bottle cap onto the motor. Now, attach the motor, on its flat side, to the bottom of the piece sticking out. Use however much wire you need to link the motor with the first battery. This will create a parallel circuit.

You can detach and reattach the wire when you would like to turn it on and off. Feel free to race your friends with this sturdy vehicle.