Force

a pull or push

Net force

The combination of forces acting on an object at any given point.

Newtons 1st Law

Objects at rest tend to stay at rest and objects in motion tend to stay in motion unless acted on by a force

Newton's 2nd law

The acceleration of an object is in the same direction as the net force acting on the object.

Gravity

An attractive force between any two objects that depends on the masses of the objects and the distance between them.

Weight

The gravitational force exerted on an object on Earth's surface.

Newton's 3rd law

States: to every action there is an equal and opposite reaction.

Momentum

The product of objects mass and velocity.

Acceleration is "________________" to mass

inversely proportional

Acceleration is "_________________" to force

directly proportiona

Acceleration due to gravity

9.8 m/s2

The equal and opposite forces are called

⇒ action and reaction forces

Law of Conservation of Momentum

If no external force acts on a closed system of objects, the momentum of the closed system remains constant

Electromagnetic Force

Act between charged objects or subatomic particles

Magnetic force

Act on certain metals, poles of magnets, and on moving charges

Strong Nuclear Force

Holds together the protons and neutrons of the nucleus

Strong Nuclear Force

Strongest universal force, acts over the shortest distance

Weak Nuclear Force

Affects all subatomic particles in the nucleus of an atom, not just protons and neutrons

Gravitational Force

Force that depends on mass and distance

Force can accelerate a moving object by changing its:

Speed, direction, or both

Gravitational Force

Weakest universal force, but it is the most effective force over long distances.

Objects with like charges ________ each other

repel

Objects with opposite charges ________ each other

attract

Electric and Magnetic

The only two forces that can both attract and repel.

The Four Universal Forces

Electromagnetic, Strong Nuclear, Weak Nuclear, Graviational

units for momentum

kg•m/s

Forces always exists in

Pairs.

Your in-line skates are sitting in a box on a shelf in the closet. What

is their momentum?

is their momentum?

Zero

According to the law of conservation of momentum, what happens to the total momentum of a system if no net force acts on the system?

The total momentum does not change.

Inertia

tendency of an object to resist a change in its motion.

Earth's gravity acts in a ________ direction

Downward

When __________ forces act on an object net force is zerio

Balanced

The friction force that acts on objects that are at rest is _________.

Static

Friction force opposing motion of an object moving through fluid

Fluid

Friction force that opposes the motion of objects sliding.

Sliding

Unit of measure for force.

Newtons