Test Your Understanding

1) Rockets are unable to accelerate in space because ....

2) Is it true that you cannot move a football by kicking it because the reaction force of the ball would be equal and opposite to the force of your foot.The net force would be zero, so no matter how hard you kicked the ball wouldn't move?

3) In the top picture, a physics student is pulling on a rope which is attached to a wall. In the bottom picture the physics stutent is pulling upon a rope which is held by a strong man. In each case, the force force scale reads 500 newtons. The physics student is pulling.... . . ..