Newton's third law, the wagon exerts an equal and opposite force of 400N. Since the two forces are in opposite directions, why don't they cancel each other and produce zero acceleration?
2006-11-23 16:21:39 · 2 answers · asked by suhel 1 in Science & Mathematics ➔ Physics
They cannot. They are acting on different bodies. The force exerted by the horse acts on the wagon, that exerted by the wagon acts on the horse. The forces are NOT colinear, which is a conditon for 'cancelling'
2006-11-23 16:25:38 · answer #1 · answered by Anonymous · 0⤊ 0⤋
The source of the wagon's opposite force is its inertia. The horse's pull causes acceleration measured by a = F/m.
If the wheels were frozen in ice, then the source of the opposite force would be the ice, and there would need to be another equal and opposite pair between the ice and the earth - a stationary object.
2006-11-24 04:22:21 · answer #2 · answered by sojsail 7 · 0⤊ 0⤋