Physics Vocabulary Final

Acceleration

The rate at which an object’s velocity changes

Free fall

The motion of falling objects when air resistance is negligible

acceleration

The slope of a tangent line on a velocity-time graph

Displacement

The area under a velocity-time graph is equal to the object’s

velocity

The slope of a tangent line on a displacement-time graph is equal to the object’s

terminal velocity

the point where the force of air resistance equals the force of gravity

free fall

is motion with no acceleration other than that provided by gravity

mass

the amount of matter in an object, is a scalar quantity

weight

is the gravitational force experienced by an object, is a vector quantity

contact force

forces that are exerted when two objects make contact with each other

field force

forces that are exerted without the contact of two objects

first law of motion

law of inertia, an object at rest remains at rest or in motion at a constant velocity unless acted upon by an external force.

second law of motion

The acceleration of an object is directly proportional to the net force applied to it, and inversely proportional to the mass of the object.

third law of motion

for every action there is an equal and opposite reaction.

inertia

is the tendency of an object to resist changes in velocity

equilibrium

when the net force on an object is zero

precision

is the degree of exactness of a measurement;

accuracy

describes how well the results of a measurement agree with the “real” value.

independent variable

is the variable that is changed or manipulated

dependent variable

the variable that depends on the independent variable.

dimensional analysis

the method of treating the units as algebraic quantities that can be canceled

vector

a quantity with both magnitude and direction.

scalar

a quantity that has only magnitude

distance

measures the length between objects or points without regard for direction.

displacement

the change in position of an object

speed

the rate of change of position of an object in any direction, is a scalar quantity

velocity

the rate at which an object changes its position, is a vector quantity

average speed

is the total distance traveled by the object in a particular time interval, is a scalar quantity.

average velocity

the change in position or displacement (∆x) divided by the time intervals (∆t)

Centripetal force

a force directed toward the center of a circle

Uniform circular motion

the movement of an object at a constant speed around a circle with a fixed radius

Centripetal acceleration

acceleration that always points toward the center of a circle

trajectory

projectile’s path through space

reference frame

a coordinate system for motion

projectile

an object shot through the air

projectile motion

is an object moving in two dimensions under the influence of earth’s gravity.

range

is the horizontal displacement of the projectile.

maximum height

is the vertical displacement of the projectile.

angular velocity

is the time rate at which an object rotates or revolves about an axis

Instantaneous velocity

the speed and direction of an object at a particular instant

Velocity vector

is tangential

Horizontal displacement

range

Vertical displacement

maximum height