Today most scientists, in almost all countries use the International System of Units (SI units) as their system of measurement.

Unit 1: Nature of Science. Measurement.

Reason 1: helps scientists share and compare their data/ results

Reason 2: Another advantage of SI units is all units are based on the number 10; meaning they are

easily converted from one unit to another

Unit 1: Nature of Science. Measurement.

Length: the distance from one point to another

Basic SI Unit of length: meter Base unit symbol: m

Tool used to measure length: meter stick

Volume: The amount of space that matter occupies.

VOLUME OF A LIQUID

Basic SI Unit of liquid volume: liter

Base unit symbol: L

Tool used to measure liquid volume: graduated cylinder

Unit 1: Nature of Science. Measurement.

Volume of REGULARLY SHAPED SOLID OBJECTS

Basic SI Unit of solid volume: cubic centimeter Base unit symbol: cm3

Tool used to measure solid volume: meter stick To calculate solid volume: L x W x H

Unit 1: Nature of Science. Measurement.

Unit 1: Nature of Science. Measurement.

Mass: is the amount of matter that something is made of

Basic SI Unit of mass: gram

Base unit symbol: g

Tool used to measure mass: triple beam balance

Volume of an Irregularly Shaped Object

Basic SI Unit: cubic centimeter

Base unit symbol: cm3

Tool used to measure volume of irreg. solid: graduated cylinder

Unit 1: Nature of Science. Measurement.

Water Displacement method:

Volume of liquid after object has been submerged - Original Volume of liquid in grad. Cylinder

Answer is volume of irregular solid object (cm3)

Unit 1: Nature of Science. Measurement.

Dora Example 48 mL -44 mL 4cm3

***BECAUSE 1mL = 1cm3

Unit 1: Nature of Science. Measurement.

Weight: is a measure of the force of gravity on an object

Basic SI Unit of weight: Newton Base unit symbol: N

Tool used to measure weight: spring scale

Mass DOES NOT change with location, weight DOES!

Unit 1: Nature of Science. Measurement.

Mass vs. Weight

Temperature: is a measure of how hot (or cold) something is. Specifically, the measure of average kinetic energy of the particles in

the object.

Unit 1: Nature of Science. Measurement.

Basic SI Unit of temperature: Degrees Celsius

Base unit symbol: °C

Tool used to measure temperature: thermometer

Time: the measure of a passing interval, from one event to another

Unit 1: Nature of Science. Measurement.

Basic SI Unit of time: second

Base unit symbol: s

Tool used to measure

time: stopwatch

Density the amount of “stuff” in a particular space - The density of room temp. water is 1 gram/ cm3

- An object will SINK in water if an objects density is greater than 1 g/cm3.

- An object will FLOAT in water if its density is less than 1 g/cm3 it will.

- Density = mass volume

Unit 1: Nature of Science. Measurement.

An objects density does NOT change when it is broken in half! The molecules are still packed in the same way, no matter the size of the sample. D= m/v

D= 60 g/25cm3

D= 2.4 g/ cm3

D= m/v D= 120 g/ 50cm3 D= 2.4 g/ cm3

D= m/v D= 96 g/ 40cm3 D= 2.4 g/ cm3

Unit 1: Nature of Science. Measurement.