Introduction to SI Units and Measurement Techniques

These flashcards cover essential vocabulary related to the International System of Units (SI), measurement techniques, and basic concepts in environmental science.

International System of Units (SI)

A standard system of measurement used globally, based on multiples of 10.

Accuracy

How closely a measurement agrees with the true or accepted value.

Precision

How closely repeated measurements are to each other.

Meter (m)

The basic unit of length in the metric system.

Kilometer (km)

A unit of length equal to 1000 meters.

Centimeter (cm)

A unit of length equal to 1/100th of a meter.

Millimeter (mm)

A unit of length equal to 1/1000th of a meter.

Micrometer (µm)

A unit of length equal to 1/1,000,000th of a meter.

Liter (L)

The basic unit of volume in the metric system.

Milliliter (ml)

A unit of volume equal to 1/1000th of a liter.

Metric ton (t)

A unit of mass equal to 1000 kilograms.

Kilogram (kg)

A unit of mass equal to 1000 grams.

Gram (g)

The basic unit of mass in the metric system.

Accuracy vs. Precision

Accuracy refers to closeness to true value; precision refers to consistency among measurements.

Celsius scale

A temperature scale used worldwide, where 0°C is freezing and 100°C is boiling.

Fahrenheit scale

A temperature scale used primarily in the United States, where 32°F is freezing and 212°F is boiling.

Meniscus

The curve at the surface of a liquid in a container, used for accurate volume measurement.

Tare

The process of zeroing a balance before measuring the mass of a sample.

Conversion factor

A numerical factor used to convert between units.

Standard system of measurement

A system that provides a consistent framework for quantifying physical quantities.

Mass

A measure of the amount of matter in an object, typically measured in grams or kilograms.

Length

A measure of the extent of an object in one dimension, measured in meters or its subdivisions.

Volume

The amount of space occupied by a substance, measured in liters or cubic centimeters.

Sample size (n)

The number of observations or replicates used in an experiment.

Diameter at breast height (DBH)

A standard measurement of tree diameter, taken at 1.3 meters above ground.

Chemical balance

An instrument that measures the mass of substances accurately.

Graduated cylinder

A laboratory instrument used to measure the volume of liquids.

Pipet

A laboratory tool used to transport a measured volume of liquid.

Calibration

The process of adjusting an instrument to ensure its accuracy.

Electronic balance

A digital scale used to accurately measure mass.

Micropipette

A laboratory tool used to transfer small volumes of liquid, usually in microliters.

SI unit

A unit defined by the International System of Units.