One day, Bobby went out for a walk. Whenever he steps forward, it causes his foot to slide across the ground for a second. Sliding friction causes him to be able to gain traction on the ground and push his body forward.
Ah, what a beautiful day!
All of the sudden, he tried to step forward on a block of ice, but he slips and falls due to a lack of sliding friction. The force of gravity pushes him down to the ground, increasing the pain of the fall. Poor Bobby.
After hearing Bobby call out in pain, Mr. Tim runs over to help and slips on the ice as well due to the lack of friction. Since his weight is a lot higher then Bobby's, he falls to the ground even harder right on top of Bobby. Ouch