AP physics - Chapter 1
Displacement
A change in position
Origin
A fixed point
Atomic model
A model of how the atoms are made
Model
A particle
A particle doesn't have what?
A particle has no size, no shape, and no distinction between top and bottom or between front and back
Vector quantity
A quantity that has both size and direction
Conversion factor
A ratio of values equal to 1
Motion diagram
A series of images showing the positions of a moving object at equal time intervals
Particle model
A simplification in which we treat a moving object as if its mass were concentrated at a single point
Velocity
A vector quantity that includes the speed and direction of an object.
Particle
An object that can represent as a mass at a single point in space
Fact 2
An object's displacement vector is drawn from the object's initial position to its final position regardless to the actual path followed between the two points
Fact 3
An object's velocity vector points in the same direction as its displacement vector
Coordinate System
An origin and an axis marked by both the positive and negative directions
What are some examples of motion?
Bicycles, cars, baseball, airplanes
Time intervals
Changes in time
Order-of-magnitude estimate
One-significant-figure estimate or calculation
How are many concepts in physics introduced
Operational definitions
Velocity vector
Points in the direction of the object's motion, and whose magnitude is the object's speed
Displacement vector
Since displacement is a quality that has both size and direction
Fact 1
Speed measures how fast an object moves, but velocity tells us both an object's and its direction
What are the basic types of motion?
Straight-line motion, Circular motion, Projectile motion, and Rotational motion
Motion
The change of an object's position or orientation with time
Operational definitions
The concepts are defined in terms of a procedure or operation preformed by the investigator
Significant figures
The number of digits that are important
Trajectory
The path along which an object move, which might be straight or curved
Magnitude
The size or length of a vector
Coordinate
The symbol that represents the position along an axis
Scalar quantity
When a physical quantity is described by a single number
Uniform motion
When an object neither speeding up nor slowing down
Position
Your position at a particular moment in time
What is the equation for speed?
speed=(distance traveled in a given time interval)/(time interval)
What is the equation for velocity?
velocity= (displacement/time interval)=∆x/∆t
