# Scientific Measurement SCIENTIFIC MEASUREMENT

Metric System

(international system of units or SI)

- A decimal system (based on 10) that scientists and everyone else in the world uses, except the U.S.

LENGTH

Meter - basic unit of length. A little more than 3 feet. Use to measure a room.

Kilometer - = 1000 meters. Use to measure long distances. About 2/3 of a mile.

Centimeter - 100 cm = 1 meter. Use to measure smaller objects, like a bird.

Millimeter - 1000 mm = 1 meter. Use to measure even smaller objects, like the pupil of an eye.

Micrometer - 1 million = 1 meter. Use to measure microorganisms.

Nanometers - 1 billion = 1 meter. Use to measure very small organisms, like viruses.

VOLUME

The amount of space an object takes up is called its volume.

Liter - (L) the basic unit of volume in the metric system, slightly larger than the quart.

Milliliter-(mL) 1/1000 of a liter: 1000 mL= 1 L

Use L and mL to measure liquids and gases.

MASS AND WEIGHT

Kilogram - (Kg): a little more than 2 lbs.

Gram - (g): 1/1000 of a Kg. 1000 g = 1

Kg

Milligram - (mg): 1/1000 of a gram

MASS VERSUS WEIGHT

Mass is not equal to weight

Mass - the measure of the amount of matter in an object. Is constant

Weight - is a measure of the force of attraction between objects due to gravity.

Is not constant.

DENSITY

The measurement of how much mass is contained in a given volume of an object.

Density=Mass/Volume

Every substance has its own characteristic density.

TEMPERATURE

Scientist use the Celsius scale

0 degrees = the freezing point of water.

100 degrees = boiling point of water.

QUICK QUIZ

1. What are 2 benefits of using the

International System of Units?

2. What is the basic unit for length? For mass? For volume?