This week we have been investigating which materials make good insulators. An insulator is a material which doesn't let heat in or out. We read a book called The Snowman's Coat, in which some children were trying to make their snowman last for as long as possible without melting. They wondered if putting a coat on it would help. Rusty thought it would make the snowman melt more quickly, Jo thought that it would keep it cold and make it last longer and Alex thought that it would make no difference.
What do you think?
We planned our own investigation to see what would have happened. Instead of snow, we used blocks of ice and to make it a fair test, each block was the same shape and size. In groups, we then chose different materials to make coats out of and finally, we wrapped the blocks of ice in those materials. The materials we chose were: baking paper, cling film, fleece, cotton wool and tin foil. We also left one block without a coat so that we could compare it with the others.
Which one do you think lasted the longest?
At the end of the day, we took all the coats of to see what was left of our snowmen, and which (if any) materials had kept the ice from melting too much.
The cling film didn't do a very good job
The fleece coat helped the ice to stay quite cool
The baking paper didn't make much difference at all
Cotton wool seemed to stop the ice from melting too much
It looked like tin foil did the worst job of all!
We discovered that the two materials which made the best coats for our snowmen, stopping too much heat from melting the ice were the cotton wool and the fleece. After a whole day in the classroom, both snowmen were doing quite well!