1. Forces Part 2 Created by: Faith Cohen/2009 Newton’s Third Law

2. Balanced Forces Two or more opposite forces are balanced if their effects cancel each other and do not cause a change in an object’s motion.

3. If 2 forces of equal strength act upon an object in opposite directions, the forces will cancel, resulting in a net force of zero. NO MOVEMENT will take place. If 2 forces of equal strength act upon an object in opposite directions, the forces will cancel, resulting in a net force of zero. NO MOVEMENT will take place.

4. If the effects of the forces DON’T cancel each other, if one force is stronger than the other, the forces are UNBALANCED FORCES. Unbalanced forces cause a change in motion, speed and/or direction. If the effects of the forces DON’T cancel each other, if one force is stronger than the other, the forces are UNBALANCED FORCES. Unbalanced forces cause a change in motion, speed and/or direction. Unbalanced Forces

5. When 2 forces act in the same direction on an object, the net force is the sum of the 2 forces. When 2 unequal forces act in opposite directions on an object, the net force is the difference of the 2 forces.

6. Forces are measured in Newtons. The higher the Newtons the stronger the force. Forces are measured in Newtons. The higher the Newtons the stronger the force.

7. 500 Newtons 1) The forces shown are PUSHING/PULLING forces. 2) The forces shown are WORKING TOGETHER/OPPOSITE FORCES. 3) The forces are EQUAL/UNEQUAL. 4) The forces DO/DO NOT balance each other. 5) There IS/IS NOT motion.

8. 200 Newtons 75 Newtons 1) The forces shown above are PUSHING/PULLING forces. 2) The forces are WORKING TOGETHER/OPPOSITE FORCES. 3) The forces are EQUAL/NOT EQUAL. 4) The forces DO/DO NOT balance each other. 5) The stronger force is pulling to the RIGHT/LEFT. 6) Motion is moving to the LEFT/RIGHT.

9. Assignment Create 2 illustrations. One showing balanced forces and one showing unbalanced forces. Do not use a tug of war picture.