Newton’s 1st Law

Newton’s : INERTIA

An object will stay ,

an object will stay in ,

an object moving will

continue moving ,

acted upon by an outside net force.

If a block that had been sitting on a table moves,

look for that caused it to change.

If a block that had been traveling in a straight

line its direction,

look for that caused it to change.

If a satellite does not travel in the

direction and at speed for all eternity,

look for a net force that.

, if an object is not changing,

there is no force acting on it.

force is not the same as force.

An object have no net force if there are forces acting on it.

An object can have no

force if all of the forces acting on it each other out.

Forces have .

Therefore, force is a quantity.

It has both and .

What are some other vector quantities? Name some scalar quantities.

I

won’t change unless it is to change

stubborn

Make me!

and are the same thing.

Mass and inertia are the .

The inertia an object has, the force it will need to

change its motion (or motion).

So, force and inertia are proportional.

Inertia and mass are the same thing.

The more mass an object has the it will need to change its

motion (or lack of motion).

Force and mass are proportional?

Inertia and mass are both measured in kilograms in the system.

CHECK YOUR UNDERSTANDING

A heavy plate is sitting on top of a table that is covered with a smooth tablecloth. You grab the ends of the tablecloth and pull very quickly. The heavy plate barely moves. Why?

CHECK YOUR UNDERSTANDING

A rocket ship in space fires a probe into empty space where there are no other forces. Will the probe slow down?

Will the probe speed up? Will the probe change direction?

Why?

CHECK YOUR UNDERSTANDING

A girl is skateboarding but she has to keep pushing on the ground in order to keep moving at the same speed. Why?

.

.

is a force.

Friction always acts to the direction that the object is moving (or wants to move).

Friction always works to an object down.

What would happen if the force of friction could speed an object up?

NO MORE ENERGY CRISIS!

Friction is an force.

(Just thought you wanted to know that.)