–
Volume
involves how much
space
an object
occupies.

Mass—A Measure of Inertia
CHECK YOUR UNDERSTANDING
The concept of inertia mostly involves
A. mass.
B. weight.
C. volume.
D. density.

Mass—A Measure of Inertia
CHECK YOUR ANSWER
The concept of inertia mostly involves
A. mass.
B. weight.
C. volume.
D. density.
Comment:
Anybody get this wrong? Check the title of this
slide!

Mass—A Measure of Inertia
•
Standard unit of measurement for mass: the
kilogram
•
One Kilogram (kg) of any material on Earth's surface
weighs 10 newtons.
•
Away from the Earth, as on the Moon or other small
bodies, 1 kg of material weighs less than 10 newtons.

Mass—A Measure of Inertia
CHECK YOUR UNDERSTANDING
When the string is pulled down slowly, the top
string breaks. This best illustrates the
A.
weight of the ball.
B.
mass of the ball.
C.
volume of the ball.
D.
density of the ball.

Mass—A Measure of Inertia
CHECK YOUR ANSWER
When the string is pulled down slowly, the top
string breaks. This best illustrates the
A.
weight of the ball.
B.
mass of the ball.
C.
volume of the ball.
D.
density of the ball.
Explanation:
The tension in the top string is the pulling tension plus
the weight of the ball, both of which break the top string.

Mass—A Measure of Inertia
CHECK YOUR UNDERSTANDING
When the string is pulled down quickly, the bottom
string breaks. This best illustrates the
A.
weight of the ball.
B.
mass of the ball.
C.
volume of the ball.
D.
density of the ball.

Mass—A Measure of Inertia
CHECK YOUR ANSWER
When the string is pulled down quickly, the bottom
string breaks. This best illustrates the
A.
weight of the ball.
B.
mass of the ball.
C.
volume of the ball.
D.
density of the ball.
Explanation:
It is the "laziness" of the ball that keeps it at rest,
resulting in the breaking of the bottom string.

•
Measure of compactness
–
Density
is the measure of how much mass
occupies a given space.
– Equation for density:
Density =
in grams per cubic centimeter or kilograms
per cubic meter
mass
volume
Mass—A Measure of Inertia

Mass—A Measure of Inertia
CHECK YOUR UNDERSTANDING
The density of 1 kilogram of iron is
A.
less on the Moon.
B.
the same on the Moon.
C.
greater on the Moon.
D.
all of the above

Mass—A Measure of Inertia
CHECK YOUR ANSWER
The density of 1 kilogram of iron is
A.
less on the Moon.
B.
the same on the Moon.
C.
greater on the Moon.
D.
all of the above
Explanation:
Both the mass and the volume of 1 kilogram of iron are
the same everywhere, so the density is the same
everywhere.

Net Force
•
Force
is simply a push or a pull.
•
Net force
is a combination of all the forces that
act on an object. It is the net force that changes
an object's state of motion.

Net Force
CHECK YOUR UNDERSTANDING
A cart is pushed to the right with a force of 15 N
while being pulled to the left with a force of 20 N.

#### You've reached the end of your free preview.

Want to read all 61 pages?

- Spring '14
- AnnM.Robinson