Apologia Physical Science Module 9 & 10

21 terms

Mechanics

study of motion, forces, and energy.

Reference Point

a point against which a position's movement is measured.

Speed

how quickly a motion occurs; a scalar quantity; distance traveled / time traveled = ________

Velocity

speed and direction; a vector quantity

Vector Quantity

a physical measurement that contains directional information

Scalar Quantity

a physical meausrement that does not contain directional information

Objects traveling in the same direction

relative speed is the diference between their individual speeds

Objects traveling in the opposite direction

relative speed is the sum of their individual speeds

Acceleration

the time rate of change of an object's velocity

Acceleration

(final velocity - initial velocity) / time = ______________.

Free Fall

the motion of an object when it is falling solely under the influence of gravity.

9.8 meters/second squared

Metric rate of acceleration due to gravity

32 feet/second squared

English rate of acceleration due to gravity

distance

___________ = 1/2 x (acceleration)(time) squared

inertia

An object's resistance to change

friction

A force that opposes motion, resulting from the contact of two surfaces

kinetic friction

Friction that opposes motion once the motion has already started.

static friction

Friction that opposes the initiation of motion

Newton's First Law

An object in motion (or at rest) will tend to stay in motion (or at rest) until it is acted upon by an outside force.

Newton's Second Law

When an object is acted on by one or more outside forces, the total force is equal to the mass of the object times the resulting acceleration.

Newton's Third Law

For every action, there is an equal and opposite reaction