Vocabulary to Know (LOS) Make sure to add lots of details to your vocabulary map including illustrations and examples

1. force: a push or pull (has direction and size) *gives energy to objects *cause a change in motion direction magnitude (size)

2. net force: combination of all the forces acting on an object Same direction: Add Opposite direction: Subtract

3. balanced forces: will not cause a change in the motion of an object (net force = 0)

More examples of balanced forces:

4.unbalanced forces: will produce a change in motion; (net force ) 0) Balanced forces combine to give a net force of zero. Unbalanced forces combine to equal a number other than zero. Example

More examples of unbalanced forces:

Try it? Balanced or unbalanced? Net force?

5. inertia: the tendency of an object to resist a change in motion (physical property) *more mass = more inertia (more force needed) *less mass = less inertia (less force needed)

Always wear seatbelts to protect yourself from the effects of inertia! Newton’s 1 st : Objects at rest remain at rest, objects in motion remain in motion – until acted upon by an outside, unbalanced force.

6. motion: an object’s change in position relative to a reference point reference point: the object that appears to stay in place What is the reference point? What is in motion?

6. motion: an object’s change in position relative to a reference point reference point: the object that appears to stay in place What is the reference point? What is in motion?

7. speed: distance / time average speed = total distance (d) total time (t)

distance in meters (m) time in seconds 564

8. velocity: the speed AND direction of an object 45 km/h east, then 45 km/h west

Practice: Tom is traveling west at 50 miles per hour. Sally and her family are traveling south at 50 miles per hour. Do the cars have the same velocity? Why or why not? TomSally

Bob is flying west at 650 km/h. Ryan is flying west at 625 km/h. Do the planes have the same velocity? Why or why not? BobRyan

Monica drives south at 60 miles per hour. Tina drives south at 60 miles per hour. Do the cars have the same velocity? Why or why not? Monica Tina

9. acceleration: the rate at which velocity CHANGES (Ex. Change in speed, direction, OR both)

Practice: Tom is traveling west at 50 miles per hour. He passes Sally while she is driving 50 miles per hour. Did Tom accelerate? Why or why not? TomSally

Bob is flying east at 650 km/h when he suddenly remembered that he forgot his passenger at the airport. While maintaining the same speed, he gently turned the plane back toward the airport to pick her up. Did Bob accelerate? Why or why not? Bob

Monica was driving south at 60 miles per hour. When it got to be lunch time, she pulled off at the next hamburger joint and went in to get a quick bite. Did Monica accelerate? Why or why not? Monica

velocity in m/s time in seconds

10. newton: (N) a unit for force (and weight)

11.friction: a force that OPPOSES motion between two surfaces that are in contact

12. gravity: a force of attraction between objects that is due to their masses and the distance between them