Invention Help!

[3553e]

I need to make a invention for science that uses a simple machine. I only have 2 class periods to make it, so it can't be too hard. I also have to solve a problem that would help us in everyday life. One more thing, I have to use mostly recycled materials. Any suggestions? I need them SOON!

[Mortartube]

Take a wooden box (like a tomato box from the greengrocers) and paint it black inside.

Drill a hole in two opposite sides and thread a hosepipe in and out through each hole but lay the hose in the box in S shapes like a snake so you get as much hose (in one layer) as possible into the box. (Copper pipe would be better but that's quite ambitious.)

Put a piece of clear plastic sheet over the top of the box. Connect one end of the hose to a tap. (A garden tap outside would be ideal). Make sure the other end of the hose has a nozzle so you can stop water coming out (like a garden spray nozzle).

Fill the hose with water and close the nozzle. Put the box out in the sun and it will heat the water after an hour or two. You can then have a limited supply of free hot water for scrubbing out plant pots etc, or even fill your washing up bowl indoors and do the dishes.

The bigger the box and the more hose you can thread in, the more hot water you get in one go.

You have solved the problem of getting hot water in an environmentally friendly way and the first definition here makes it a machine as it modifies the solar energy to heat water.

http://dictionary.die.net/machine