Unit 1 Vocab Review: Forces and Motion

Newton’s Third Law

When one object applies a force to a second object, the second object applies an equal but opposite force to the first object

Newton’s First Law

Unless acted upon by an unbalanced force, an object at rest will remain at rest and an object in motion stays in motion going the same speed and same direction.

Weight

The measure of the gravitational pull on an object that is measured in Newtons

Drag

The specific term used for the force on a plane that is caused by air resistance

Air Resistance

The term used for friction with the air

Terminal Velocity

The constant speed that a falling object eventually reaches when the upward force if air resistance balances the downward pull of gravity

Net Force

The combination of all the forces acting on an object

Mass

The amount of matter that makes up an object and is measured in grams

Newton’s Second Law

The acceleration of an object depends on the mass of the object and the amount of force applied. It is often expressed with the equation a=f/m or f=ma

Newton

Metric unit for measuring force. It is equal to one kg of mass accelerating at 1 m/s/s

Force

Any push or pull acting on an object

Reference Point

An object that is usually stationary and is used to judge the position of other objects, depending on their mass and the distance between the two objects.

Gravity

An attractive force that all objects have on other objects depending on their mass and distance between the two objects

Vacuum

An area that has all the air removed.

Acceleration

A vector quantity that measure the rate of change in velocity of an object. An object does this whenever it speeds up, slows down, or simply changes direction.

Velocity

A vector quantity that that measures not only the speed of an object but also its direction,

Speed

A term used to describe how long it takes for an object to cover a certain distance. It is measured by taking the distance traveled and dividing by the time it takes to go that distance.

Motion

A term used to describe an object’s change in position which depends on the reference point.

Inertia

The tendency of all objects with mass to resist a change in motion. Objects with more mass will have more of this.

Friction

A general term to describe the force that exists whenever two objects are in contact with each other. This force always opposes motion an causes all objects to slow down.