1. Combining Forces Ch2 Lesson 1 pg 88-91

2. What is a force? A force is a push or a pull Forces are always exerted by one object on another object

3. Contact Forces Contact force is a force that is exerted only when two objects are touching EXAMPLES: – Pushing a pencil across a sheet of paper to write – A tow truck that pulls a car along a street – Karate chopping pieces of wood – Using a bow and arrow

5. Noncontact Forces Noncontact force is a force that one object exerts on another when they are not touching EXAMPLES: – Magnetic force between two magnets – Gravitational force – Electric force

7. Force is a vector A vector has a size and direction Forces are described in both direction and magnitude (size), therefore force is a vector

8. Combining forces Net force is the combination of all the forces acting on an object Forces in the same direction are added together to get the net force Forces in the opposite direction are subtracted, the net force going in the direction of the larger force

12. Unbalanced and Balanced forces When the net force of an object equals zero, the forces on the object are called balanced forces When the net force of an object is not zero, the forces are unbalanced forces