Soda cans bogging you down?
Show kids how the sun affects water by creating your own *simple* solar hot water heater!
Materials: soda can (or any aluminum can), black paint, water, thermometer (for older kids)
Making Your Hot Water Heater:
- Have your kids carefully paint the outside of the can black. (You may have to do this with younger kids). Remember, this post on colors and heat? Black absorbs heat.
- Fill the can with cold water from the tap and have younger kids feel it. Older kids would benefit from learning how to read the temperature of the water on a thermometer.
- Set the can of water out in the sun for the hottest part of the day (4-5 hours works great!).
- For younger kids, feel cold tap water, then feel the water from the can. Ask them if they notice a difference. For older kids, take the temperature of the water. Has it changed? Discuss their observations and conclusions.
- And, hey, if the water is warm enough, try the experiment again and stick in a tea bag or mix in some hot chocolate! (note: to do this, I would avoid using the paint and instead cover the can in black construction paper – be sure the can is cleaned!)
Extend It: Now that you know the trick to warming up water, try these experiments:
- Try painting the cans different colors to test the sun’s affect on each colored can.
- Try filling the cans up to different water levels. Does the water heat up faster or slower?
- What liquid warms up more quickly out in the sun: water, soda, juice, tea, etc.
- Place solids in the cans and see how well they absorb the sun’s heat.
Tomorrow we’ll be showing you how to make your own little greenhouse, making use of the sun’s warm rays!