Chapter 9/10 Section 1

Motion:

When an objects distance from another object is changing

Reference Point A place or an object

used for comparison to determine if something is in motion

An object is in motion if it changes position relative to a reference point

Speed

The distance an object travels in one units time.

Speed 50 miles/hour 80.5 kilometers/hour

Speed = Distance or Distance/Time Time

When you know the speed and direction of an object’s motion,

you know the velocity of the object.

Force:

Push or pull

Force

When one object pushes or pulls another object, the first object is exerting a force on the second object.

Balanced and Unbalanced Forces

So if two forces act in the same direction they then add together

When forces act in opposite direction they combine by subtraction

If one force is greater than the other the overall force is in the direction of the greater force

The overall force on an object added up is called the net force

Unbalanced Forces

Can cause an object to start moving, stop moving or change

directions.

Balanced Forces

Equal forces acting on one object in opposite directions.

Inertia

The tendency of an object to resist change in its motion

What is Newton’s First Law of Motion?

Newton’s first law of motion states that an object at rest will remain at rest and an

object that is moving at a constant velocity will continue moving at a

constant velocity unless acted upon by an

unbalanced force.

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