In A Spin
Get a propeller to spin in two different directions working like a propeller and a fan.
Suitable for kids aged 7+, with adult supervision CAUTION
- Do not put spinning propeller near peoples faces or hair. Hair could get tangled.
- Do not hold the wire on the battery for long periods without removing it. The wire and/or battery terminal may get hot.
What to do:
- Attach the propeller to the 9V motor by pushing the motors spindle into the hole at the back of the propeller. Make sure its on tightly.
- Thread one end of a piece of stripped copper wire through the hole in the square metal ring on the motor. Twist the copper wire in on itself to hold it in place. The copper wire (not the plastic coating) needs to be in contact with the square metal ring on the motor for electricity to flow and power the propeller. See picture.
- Thread one end of the other stripped copper wire through the adjoining square metal ring, then do the same as explained in the above step. You can use masking tape to hold the wires in place better.
- Hold the free end of each wire to a battery terminal, one to each terminal, and watch the propeller spin. Which way is it spinning? Is it working like a fan, pushing air out the front, or a propeller, pushing air out the back? How can you get it to spin the other way?
Why is it so?
Depending on which way the propeller is spinning, it can work as either a fan (pushing air out front), or a propeller (pushing air out back). When it spins clockwise (looking at the propeller from the front), it works like a fan. When it spins anticlockwise (looking from the front), it works like a propeller. To get it spinning in the other direction, you need to connect the wires to the opposite battery terminals. The electricity then flows the other way causing the motor to spin in the opposite direction.
Propellers, wire and motors are available from the science supply section of this website.