17 terms

# Conceptual Physics - Hewitt - Chapter 3: Newton's First Law of Motion - Inertia

#### Terms in this set (...)

natural motion
Aristotle said heavy things fell, light things rose, and planets circled because it was their _____.
violent motion
Aristotle called imposed motion _____.
external
Aristotle claimed violent motion had an _____ cause.
Copernicus
_____ postulated that the earth and the planets move around the sun.
Galileo
_____ demolished the notion that a force is necessary to keep an object moving.
friction
_____ is caused by the irregularities in the surfaces of objects that are touching.
forever
If friction were absent, a ball moving horizontally would move _____.
inertia
The property of a body to resist changes to its state of motion is called _____.
Newton's first law (law of inertia)
Every object continues in a state or rest, or uniform straight-line speed, unless acted on by a net force.
indefinitely
In the absence of forces, a moving object tends to move in a straight line _____.
mass
_____ is a measure of the material in an object and the inertia of an object.
kilograms
Mass is measured in the fundamental unit of _____.
weight
_____ is the force of gravity on an object.
newton (N)
The SI unit of force is the _____.
10 newtons
One kilogram weighs _____.
pounds
It takes 2.2 _____ to equal 1 kilogram.
no unbalanced forces act on them
Objects in motion remain in motion if _____.