Force Chapter 10.1 Standard 2: Forces a. Students know a force has both direction and magnitude. b. Students know when an object is subject to two or more forces at once, the result is the cumulative effect of all the forces. c. Students know when the forces on an object are balanced, the motion of the object does not change. e. Students know that when the forces on an object are unbalanced, the object will change its velocity (that is, it will speed up, slow down, or change direction).

What is FORCE? What is force? FORCE is a push or pull on an object Described by the magnitude and direction in which it acts. What does that make force? A vector quantity What are the units of force? Newton, N (like Sir Isaac Newton) What does force do? Changes the motion of an object! If it isn’t moving, a force can make it move. If it is already moving, a force can make it slow down, speed up, change direction, or stop. What does that sound like?

NET FORCE What if there is more than one force? Net Force The combination of all forces acting on an object. How do we determine net force? If forces act in the same direction, they work together Same Direction  Add Forces If forces act in opposite directions, they cancel each other out. Opposite Directions  Subtract Forces

Unbalanced & Balanced FORCES Forces can be either balanced or unbalanced. . . . Unbalanced Force: Causes an object to stop moving or change direction. Result in a net force and cause a change in the object’s velocity (motion) Balanced Force: Forces in equal magnitude & opposite direction. No movement / No change in velocity

Unbalanced Forces What is the Net Force for the red airplane? What is the Net Force for the green speed racer? What is the Net Force for the white truck? Are these examples of balanced or unbalanced forces? How do you know? What is going to happen to each object because of that?

Can you spot the unbalanced forces?

Balanced Forces What is the Net Force for the jet? What is the Net Force for the building? Are these examples of balanced or unbalanced forces? How do you know? What is going to happen to each object because of that?

Can you tell that these are balanced forces?

Try It Out! How is each object going to move? Tell me the NET FORCE including magnitude and direction

Try It Out! How is each object going to move? Tell me the NET FORCE including magnitude and direction

Checkpoint!