science ch 3

Newton’s First Law

An object at rest will remain at rest and an object that is moving at a constant velocity will continue at a constant velocity unless acted upon by an unbalanced force.

Newton’s Second Law

f = ma

Newton’s Third Law

If one object exerts a force on another object, then the second object exerts an equal and opposite force on the first object. (For every action there is an equal and opposite reaction.)

Law of Conservation Momentum

Momentum of an object doesn’t change unless its mass, velocity or both change. Momentum can be transferred from one object to another.

Law of Universal Gravitation

There is an attractive force acting between all objects in the universe that have mass

Friction

A force an object exerts on another object when the two slide against each other or when an object moves through a liquid or gas.

The direction friction works in

opposite of movement

How energy is lost through friction

sound and heat

Static friction

2 surfaces being pressed together

Rolling friction

the friction between a curved surface and the surface it’s rolling on

Fluid friction

the friction when a solid is moving through a liquid or gas

Sliding friction

rubbing against each other, less than static friction

Acceleration of gravity on average, on earth, at sea level

9\.8 m/s^2

Air resistance

Fluid friction from air molecules striking the leading edge

Free fall

The motion of a falling object when the only force acting on it is its weight, due to the acceleration of gravity

Projectile

an object that is thrown

What affects air resistance?

speed and surface area

What causes gravity?

having mass

Weight

a force caused by gravity

Mass

a measure of the amount of matter

Terminal velocity

the highest speed a falling object will reach

Momentum

mass x velocity: p=mv