Unit 1: Force and Motion Vocabulary

Vocabulary terms and definitions covering fundamental concepts of force, motion, and engineering design from Unit 1.

acceleration

The change in speed and/or direction per unit time.

average speed

The total distance an object travels divided by the amount of time it took the object to travel that distance.

balanced forces

When the magnitude and direction of more than one force acting on an object results in zero net force.

braking distance

The distance a vehicle travels from the moment the driver applies the brakes until the vehicle comes to a complete stop.

constraint

In engineering design, something that limits the solution to a problem.

criteria

In engineering design, the goals and the desired features of the solution. Plural of criterion.

design

To develop a plan for a product or structure.

direction

A course along which someone or something moves.

engineer

Someone who uses science and tools to build a product that solves a practical problem.

force

A push or a pull on an object that can cause a change in motion.

friction

A force that exists at the boundary between any two pieces of matter that are in contact with each other.

inertia

Matter continues in its motion or rest unless acted upon by an outside force.

kinetic energy

Energy of motion.

mass

The amount of matter in an object.

net force

The combined force (magnitude and direction) acting on an object.

Newton's First Law of Motion

An object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Newton's Second Law of Motion

The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

Newton's Third Law of Motion

For every action, there is an equal and opposite reaction.

reaction time

The time interval between the moment a driver realizes a problem and when the driver applies the brakes.

speed

The rate at which an object moves, equal to the distance traveled per time interval.

stopping distance

The total distance a vehicle travels during the driver's effort to bring the vehicle to a halt; distance traveled during the driver's reaction time plus the braking distance.

system

A group of interacting objects or processes. Every system includes components, interactions, and boundaries.

unbalanced forces

When the magnitude and direction of more than one force acting on an object give a net force unequal to zero.