Y4 talk on static electricity

Mr Howells came into school to talk Y4 on static electricity.  He explained that if you rub a balloon on a jumper it will move negative electrons to the jumper and the positive electrons to the balloon so that the balloon can stick to the wall or pick up things if it has a negative charge.  We had fun demonstrating this when we placed a balloon on our head and saw our hair stand on end. 

Also Mr Howells bought in a Van de Graaff generator which uses a moving belt to accumulate an electric charge, created through friction, in a hollow metal globe.  If you put your hand on the globe, your hair will stand on end.  Several of us tried and had great fun. 

In another experiment, carbon balls in a cylinder were placed on the generator and when it was switched on they all flew up.  When the generator was switched off, many of the carbon balls sank back down to the base of the cylinder but some remained stuck to the side.  So we put another conductor near the generator, a spark formed which caused the carbon balls to jump and then they all fell to the base of the cylinder. 

Further experiments were conducted when Mr Howells blew bubbles at the generator when it was on and they were repelled because of the negative charge.  Paper cup cake cases were placed on top of the generator and because negative and positive repel each other, the cases flew up into the air.  We rubbed cloth on a metal rod and we waved the rod over some tissue paper, which then stuck to it.  Foil worked better as it is a metal and metal is a good conductor. 

The lesson was fun and it was informative because we learnt things that we didn’t know before.  We thought Mr Howell was really great and made the lesson really interesting. 

Jolene and Michael
Year 4