Momentum

• What happens to momentum when a force acts on an object that is moving or able to move?

  A change in momentum occurs; where the force is the rate of change in momentum.
• Where should the distance be measured?

  the Perpendicular distance (d, at 90∘) from the pivot to the like of action of the force (in metres , m).
• What is the role of a gear?

  To change the force or rotational speed of a system.