The International System of Units
(SI) is the standard system used
around the world.
The standard SI unit to measure length is
the meter (m).
The meter is divided into 100 equal parts
called centimeters (cm).
The centimeter is divided into 10 equal
parts called millimeters (mm).
Long distances are measured in kilometers
(km) which is 1,000 m.
Mass is the amount of matter that
something is made of.
The kilogram is the SI unit to measure
Mass is measured with a triple balance
Unlike weight, mass does not change with
an object’s position.
Weight is a measurement of the
gravitational force on an object.
The SI unit for force is the Newton (N).
Since weight is a measure of gravitational
force, it does matter where you are.
There is 6 times less gravitational force on
the moon, so you would weight 6 times
less there.
Use spring scales to measure weight.
Density is mass per unit volume.
Density is the amount of matter it has in a
given space.
To find density (D), first measure the mass
(m) and volume (V), then divide mass by
Density is an SI derived unit (mass and volume)
Volume is the amount of space that something
Volumes of liquids are expressed as liters (L).
Graduated cylinders are used to measure
liquid volume, and also to find the volume of a
small odd shaped object. (see meniscus)
Volumes of solid objects are expressed in
cubic meters (cm3)
Area and Volume
Area is the amount of surface included
within a set of boundaries and is
expressed in square such as square
meters (m ).
The amount of space occupied by an
object is the object’s volume.
The basic SI unit of volume for a solid
object is the cubic meter (m3).
SI measurements for liquid volumes are
in milliliters (mL) or liters (L).
Temperature is a measure of the average
kinetic energy of the particles in an object.
Temperature is not determined by how
much of the substance you have.
The SI unit for temperature is Kelvin (K),
however the Celsius (C) scale is most
commonly used.