Measurement
TWO SYSTEMS
METRIC



Used in science class and
around the world
Can multiply by 10, 100,
1000, etc… to go from one
unit to another
STANDARD

Used in America

Has uneven conversion
factors (probably need to use
a chart)

Common units:

Feet, inches, yards for
distance

Ounces, cups, pints, gallons
for liquid
Common base units:

Meters for distance

Liters for liquid

Pounds for weight

Grams for mass

Fahrenheit for temperature

Newtons for weight

Celsius for temperature
Common prefixes we will see
in metric system:
CentiHectoMilliNanoKilo-
CONVERSIONS WE SHOULD KNOW:



To go from milli- to another unit:

From milli- to centi- divide by 10

From milli- to a base unit (grams, liters, etc…) divide by 1000
To go from centi- to another unit:

From centi - to milli- mutiply by 10

From centi-to base unit (grams, liters, etc…) divide by 100
To go from kilo- to another unit:


From kilo to base unit (grams, liters, etc…) multiple by 1000
From a base unit (grams, liters, etc…) to centi-, milli-, or kilo-:

From base unit to milli-, multiply by 1000

From base unit to centi -, multiply by 100

From base unit to kilo-, divide by 1000
LENGTH

Distance from Point A to Point B

Can be used to find volume of a square or rectangle

Find the length, width, and height of the object

Multiply them together (L x W x H)- they can be
interchangeable

Make sure your units are correct (cubed)

For example:

4 cm x 7 cm x 5cm =140 cm3
Volume
Boxes and rectangles as described on the previous
slide
 Irregular objects (round, bumpy, triangular, etc…)


Water displacement method:

Fill graduated cylinder with a volume of liquid (lets say 30 ml)

Drop a ring into graduated cylinder and observe how far the water
rose (lets say 70 ml)

Subtract the starting volume (30 ml) from the ending volume (70 ml)
and it will tell you the object’s volume. In this case 40 ml.


Because it’s a solid, you need units to represent that.

1 ml= 1 cm3, so if I have 40 ml this is 40 cm3
Remember you need to read the meniscus (or curved line of water)
for an accurate reading
To read the meniscus, you want to be eye
level to the container and take the reading
at the bottom of the curve
Weight

Measure of how much gravity acts on an object

We use pounds everyday, however in science we
use Newtons

This will change based on where you go in the
universe


Because each planet or planetary body has it’s own
gravitational force

So if you go somewhere with more gravity, you will weigh more

If you go somewhere with less gravity, you will weigh less
Use a scale to measure
MASS

Measure of how much stuff is in an object

We use grams


This will not change based on where you
go in the universe

Because unless you lose part of yourself your mass will
not change

So if you go somewhere with more gravity, you will
have the same mass

If you go somewhere with less gravity, you will have the
same mass
Use a balance to measure
FUN FACT: On Earth, mass
and weight are used
interchangeably in
everyday life
ACCURACY and PRECISION
 Accuracy:

How close you are to the actual measurement

So if a book has a length of 15 centimeters, it is how many times you
ARE CLOSE TO 15 cm.
 Precision:

How many times you receive same result in your data

How many times you get the same result with a piece of
equipment.

So if you receive 15 cm, 5 times, you have some precision to your
measurement