Before we start, we'd like to point out that this isn't gory or graphic or anything of the sort.
You will, however, wince. Because this looks like it hurt. A lot. A LOT. A LOT. A LOT. A LOT.
This physics teacher was showing his class one of the fundamental precepts of physics - the relationship between inertia and conserved energy.
It's a particularly well-known experiment that places a cinder-block on the chest of a person with a nail-board held on the chest.
Another person stands over the cinder-block and smashes it, thus demonstrating one of the key principles in physics.
Anyway, this demonstration didn't exactly go according to plan as you'll see.
It's understood the physics teacher wasn't too badly injured and continued the class as normal. However, unconfirmed reports suggest that the teacher has been let go from his job.
As we said earlier, this is a common demonstration for physics teachers.
Here's how it's supposed to go, minus the ball-smashing, and a little bit of science to explain it all.
Via YouTube
