Chapter 2 Physics Vocab

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 equal time intervals

particle model

a model where you replace the object or objects of interest with single points

dimension

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

coordinate system

gives the location of the zero point of the variable you are studying and the direction in which the values of the variable increase

origin

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

position

the distance and direction from the origin to the object

distance

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

magnitude

size

vector

A quantity that has both magnitude and direction

scalar

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

time interval

the difference between two times

displacement

a change in position

resultant

a vector that represents the sum of two other vectors

intersection

a point where lines meet and cross

position-time graph

graph in which time data is plotted on a horizontal axis and the position data is plotted on a vertical axis

instantaneous position

the position at a particular instant

absolute value

magnitude of a number, regardless of sign

average velocity

the ratio of an object's change in position to the time interval during which the change occured

average speed

the slope's absolute value, which is the distance traveled divided by the time taken to travel that distance

instantaneous velocity

the speed and the direction of an object at a particular instant