While teaching STEM Club these past few weeks, I came to realize the kids were not as familiar with the forms of energy as I had predicted. I thereby decided to take a detour – exploring the differences between potential and kinetic energy in a little more depth.
We thereby did two activities this week – one to explore how the height of a swinging mass is related to its energy (or ability to do work) and another to explore how wind generates mechanical energy. I am excited to share these activities with you today.
How will the height from which an object falls affect the distance another object moves when struck?
- Clamp or Duck Tape
- 50 gram mass
- Block of Wood
- Tie one end of the string to a 50 gram mass (perhaps a D-cell battery).
- Attach the clamp to the edge of your table. Tie the loose end of the string to the clamp. Alternatively, you can use Duck Tape to secure the string to the edge of a table.
- Adjust the string so that the mass almost touches the floor. Make a small pencil mark on the floor under the mass.
- Set a block of wood on the mark. Practice swinging the mass so that it knocks the wood straight across the floor.
- While keeping the string tight, pull back the mass until it is exactly 10 cm above the floor.
- Let the mass swing down and hit the wood.
- Measure how far it moves from the mark on the floor and record the distance in the table below.
- Repeat steps 5-7 three times and calculate the average distance the block traveled.
- Raise height to 15cm and finally 20cm – repeating steps 5-7 again.
- In what way was work done in this activity?
- Where did the energy to do this work come from?
- At which height was there the most energy to do the work?
Wind Powered Cars
We converted toy cars into wind-powered cars by building and attaching turbines. Students made modifications to help their cars travel as fast as possible. In the end, we evaluated the advantages and disadvantages of wind energy.
- Turbine pattern printed onto card stock
- Jumbo paperclip
- Duct tape
- Toy car
- Place a toy car on a flat surface. Ask students to suggest ways to make it move without touching it. Ideas may include attaching a motor or knocking something into it. If this were a real car, what would give it power? Gasoline (fossil fuels) Are there some other alternative resources we could use that are renewable? Students may be most familiar with solar energy.
- Explain that students will be using wind to power a toy car.
- Cut out the turbine pattern as indicated and attach to the back of the toy car as described.
Science Logic: Electricity & Magnetism
These lessons – including lab sheets with data tables, detailed instructions for how to convert the toy cars, and activities to explore watt usage at home – will be included in the Science Logic: Electricity & Magnetism unit that I hope to release by Summer 2016.
Until then, they are available as a freebie For Subscribers Only.