A push or pull on an object.

Described by:

A force gives an object energy to:

•STRENGTH•DIRECTION

•STOP MOVING•START MOVING•CHANGE DIRECTION

The SI unit for force is the

The symbol for Newton is

One Newton = about the force you exert to lift a lime.

Named after:

NEWTON

N

Sir Isaac Newton (founder of physics)

Contact Force

Non Contact Force

A push or pull on one object by another that is touching it.

Contact forces can be:

Strong

OR

WeakExample:

FRICTION= force that opposes motion between two surfaces in

contact.

A force that one object can apply to another object without touching it.

Examples Include:

Gravity- universal attraction between all objects.

Magnetism- attracts and repels objects

An attractive force that exists between all objects that have mass. ◦ Weight is a measure of the force of gravity acting upon an

object.

On EARTH the force of gravity = 9.8 m/s2

All objects fall to the Earth at an acceleration of 9.8m/s2 due to the force of gravity.

The amount of matter in an object.

Weight and mass are related, but ARE NOT the same.

Weight can due to

Mass change

CHANGE GRAVITY

DOES NOT

can be used to show forces.

The of an arrow shows the

of the force.

The that the arrow points shows the direction in which the

The stronger the force the thearrow.

ARROWS

DIRECTION

LENGTH

STRENGTH

FORCE WAS APPLIED

LONGER

The combination of all the forces acting on an object.

To calculate the net force:

◦ If the forces act in the same direction they are added together.

◦ If forces act in opposite directions they are subtracted.

DO THE MATH pg 191, #13. Do with shoulder partner.

Forces acting on an object that combine and form a net force of ZERO. NO change in motion.

Forces acting on an object that combine and form a net force that is not zero.

Unbalanced forces cause an object to move.

Forces moving in the same direction are

Forces moving in the opposite direction are

ADDED

SUBTRACTED

FORCE= MASS x ACCELERATION

F= maForce measured in NEWTONS

Mass measured in KILOGRAMS

Acceleration measured in M/S2

DO THE MATH pg 195….RACE!

Weight and mass are related, but ARE NOT the same.

Weight can due to

Mass change

CHANGE GRAVITY

DOES NOT

F =

Weight on Earth =

M x A

MASS x 9.8m/s2 (acceleration due to the force of gravity)