Equal and Opposite but Not Balanced
Because action and reaction forces are equal and opposite, you might think
they would cancel out, as balanced forces do. But you would be wrong.
Balanced forces are equal and opposite forces that act on the same object.
That's why they cancel out. Action-reaction forces are equal and opposite
forces that act on different objects, so they don't cancel out. In fact, they often
result in motion. Think about Jerod again. He applies force with his foot to the
ground, whereas the ground applies force to Jerod and the skateboard,
causing them to move forward.
If the forces are equal and opposite, why do they not cancel out?