1. Newton’s First Law
(law of inertia)

2. Newton’s First Law (law of inertia)
An object at rest will continue to stay at rest unless an outside force acts on it and …

3. Newton’s First Law (law of inertia)
an object in motion will continue to stay in motion at constant speed in a straight line unless an outside force
acts on it

4. Newton’s First Law (law of inertia)
FORCE is a push or a pull applied to an object that will cause it to start moving, stop moving or change its speed or direction

5. Newton’s First Law (law of inertia)
FRICTION is the force that acts in the opposite direction of the motion of the object

6. Newton’s First Law (law of inertia)
MASS is the measure of the amount of matter in an object
measured in grams (g)
or kilograms (kg)

7. Newton’s First Law (law of inertia)
WEIGHT is a measure of the force of gravity on the mass of an object
measured in Newtons (N)

8. Newton’s First Law (law of inertia)
WEIGHT =
MASS
GRAVITY x
MASS =
WEIGHT
GRAVITY /

9. Newton’s First Law (law of inertia)
INERTIA is a property of an object that describes how hard it is to change the motion of the object
more mass means more inertia

10. REVIEW QUESTIONS What is the difference between mass and weight?
Which has more mass, 12 g of feathers or 12 g of lead?
When an astronaut is living on the International Space Station, what happens to his mass?

11. REVIEW QUESTIONS
What would the mass of a dog be if it has a weight of 100N?
What would the weight of an apple be if it has a mass of 1.5 kg?
What is a force?

12. REVIEW QUESTIONS What is friction?
What causes friction on a moving object?