Physics Chapter 2 Vocab

Absolute value

magnitude of a number, regardless of sign

Average speed

the distance traveled divided by the time taken to travel that distance; for uniform motion, it is the absolute value of the slope of the object's position-time graph

Average velocity

the ratio of an object's change in position to the time interval during which the change occurred; for uniform motion, it is the slope of the object's position-time graph

Coordinate system

a system used to describe motion that gives the zero point location of the variable being studied and the direction in which the values of the variable increase

Dimension

extension in a given direction; one dimension is along a straight line; three dimensions are height, width, and length

Displacement

a change in position having both magnitude and direction; is equal to the final position minus the initial position

Distance

the entire length of an object's path, even if the object moves in many directions

Instantaneous position

the position of an object at any particular instant

Instantaneous velocity

a measure of motion that tells the speed and direction of an object at a specific instant

Intersection

a point where lines meet and cross

Magnitude

a measure of size

Model

A representation of an idea, event, structure, or object to help people better understand it.

Motion diagram

a series of images showing the positions of a moving object at regular (equal) time intervals

Origin

the point at which both variables in a coordinate system have the value zero

Particle model

a simplified version of a motion diagram in which the moving object is replaced by a series of single points

Position

the distance and direction from the origin to the object

Position-time graph

a graph that can be used to determine an object's velocity and position, as well as where and when two objects meet, by plotting the time data on a horizontal axis and the position data on a vertical axis

Resultant

a vector that represents the sum of two other vectors; it always points from the first vector's tail to the last vector's tip

Scalar

a quantity, such as temperature or distance, that is just a number without any direction

Time interval

the difference between two times

Vector

a quantity, such as position, that has both magnitude and direction