1
Difference Between Weight and Mass
Gravitational conversion g
c
Dimensional Consistency
Mass, Moles, and MW
Density, Specific Gravity, Specific Volume
Types of Pressures
Lecture Topics
Though the terms
weight
and
mass
are used interchangeably
in common language, in science there is distinct difference
between the two terms.
weight
of an object = force of gravity felt by that object
mass
of an object = the amount of matter the object has.
Mass and Weight
An object's weight depends on the pull of the gravitating object
but the object's mass is independent of the gravity.
weight
on the Moon = 1/6
weight
on Earth
Weight = mass * gravitational acceleration = mg
g = 9.8066 m/s
2
g = 980.66 cm/s
2
g = 32.174 ft/s
2
Another way to look at it is,
mass is a measure of the object's
resistance to acceleration: a push on a skateboard will make it
roll away quickly but the same push on a more massive car will
barely budge it.
Newton’s Second Law
Force = mass * acceleration
F
= m * a
In the old English unit system, there is a ``pound'' of force
(lb
f
)
and ``pound'' of mass (
lb
m
). Only on the Earth's surface, an
object's pound of mass = the number of pounds of force felt by
the object due to the Earth's gravity.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Fall '11
 STAFF
 Mass, Kilogram, in2, Centimetre gram second system of units, g/cm3

Click to edit the document details