dangerous decibels

To day in the middle block me and my class went and learnt about dangerous decibels with Toni. She told us that sound is dangerous is it is to loud. We got these things called churning fork and we whacked against the floor and put it up to our ears and it made a funny high pitched sound. Then we got this ping pong ball that was attached to a piece of string and then we whacked the churning fork on the ground and put the end on the ping pong ball and it did flips and stuff.