what the heck is metricks (metrics)

What the Heckis Metricks (Metrics)

Metrics is the Language of Science

By measuring, scientists can express their observations more precisely and communicate more information about what they observe.

Metrics is worldwide

The standard system of measurement used by scientists around the world is known as the International System of Units, which is abbreviated as SI

Systeme International d’Unites in French

Metrics is actually easier than English Units

Click here to access video clip on metrics

SI units are easy to use because they are based on multiples of 10.

Each unit is 10 times larger than the one before.

Each unit is 10 times smaller than the next unit.

Some nifty prefixes

Common SI PrefixesPrefix Symbol Meaningkilo k 1,000

hecto h 100deka da 10

deci d 0.1 (one tenth)centi c 0.01 (one hundreth)milli m 0.001 (one

thousandth

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Measuring Length

The meter (m) is used to measure length or distance between two points.

The distance from the floor to a doorknob is about one meter.

Measuring Length

Long distances are measured in kilometers (km)

The distance from Orion to Kirt’s Drive In is about 1 kilometer.

Measuring Length

Small lengths are measured in centimeters (cm) or millimeters (mm).

The width of your finger is about one centimeter.

The thickness of a dime is about one millimeter.

Measuring Length

Length can be measured with a meterstick, a ruler, or a measuring tape.

Measuring Length

Try it out…

Measure the width of your hand. What is the width in

centimeters? What is the width in

millimeters?

What is the diameter of a penny?

Measuring Mass

To measure the amount of matter in an object, we use the gram (g).

One gram is approximately the mass of a paper clip.

Measuring Mass

Large objects are measured in kilograms (kg).

One liter of bottled water weighs about one kilogram.

The average 7th grader measures about 45 kg.

Measuring Mass

Small masses are measured in milligrams.

One Tylenol pill is usually about 100 milligrams.

Measuring Mass

Mass is usually measured with a balance, like a triple beam balance.

Or a digital scale can be used.

Measuring Mass

Try it out…

What is the mass of a penny?

What is the mass of a seashell?

Measuring Liquid Volume

The liter (L) is used to measure the amount of space that a liquid takes up.

Liquid soda-pop often comes in 2-Liter bottles.

Measuring Liquid Volume

Small volumes are measured in milliliters (mL).

Vaccinations are measured in milliliters.

Measuring Liquid Volume

Scientists use graduated cylinders to measure liquid volume.

Sometimes they are also called beakers.

Measuring Liquid Volume

When using a graduated cylinder, the liquid often “sticks” to the sides of the cylinder.

This forms a curved surface on the top of the liquid, known as a meniscus.

Always measure at the bottom of the meniscus.

Measuring Temperature

Scientists measure the temperature of a substance using the Celsius scale.

Temperature is measured in degrees Celsius (oC) after the guy who came up with the idea of using degrees to measure temperature.

Measuring Temperature

Temperature is measured using a Celsius thermometer.

Water freezes at 0oC and boils at 100oC.

Measuring Temperature

You try it…

What is the temperature of this room?

What is the temperature of the human body?

Measuring Time

The unit scientists use to measure time is the second (s).

This is the same as English units

How many seconds in a minute?

How many minutes in an hour?

Measuring Time

Try it out…

Practice using the stopwatch.

How long does it take you to complete three “breath cycles” ?

(breathing normally)

Scientific Notation

When we measure things that are really big, or really small, we use scientific notation.

One meter in scientific notation would be1.0 x 100 mOne kilometer in scientific notation would be 1.0 x 103m

(we had to move the decimal back 3 spaces to get back to 1.0)

Powers of 10

Click on the title to take a fantastic trip from the smallest atom to the outer reaches of outer space.

Notice the scientific notation at each stop.