The Metric System

Background Information

• Used all over the world (except USA)

• Common language of scientists• Based on 10s• S.I. Units: International System—

standard units agreed upon by everyone.

Linear Measurement• Definition:

– Measuring in line (distance, length, width, etc.)• S.I. Unit:

– Meter (m)• Common Units:

– Centimeter (cm) 100 cm = 1 m– Millimeter (mm) 1000 mm = 1 m– Kilometer (km) 1000m = 1 km

• Tools:– Meter stick, ruler

Measurements are always read to the certain markings AND then estimated one place beyond that marking.

cm 1 2 3 4 5 6

cm 1 2 3 4 5 6

This line reads as 3.5 cm

This line reads as 2.85 cm

Volume Measurement

• Definition: – The amount of space an object takes up

• S.I. Unit:– NO S.I. unit

• Common Units:– Liter (L or l)– Milliliter (mL or ml) 1000 mL = 1 L– Cubic centimeter (cm3) 1 cm3 = 1 mL

• Tools:– Graduated cylinder or ruler

• Other facts/notes– Meniscus: the curve that forms on the

surface of a liquid.

Meniscus

– Read volume at the BOTTOM of the curve

Temperature Measurement• Definition:

– The measure of the motion of particles in a substance. The more motion, the higher the temp.

• S.I. Unit:– Kelvin (K)

• 0 K = absolute zero• 0 K = -273 oC

• Common Units:– Degrees Celcius (oC)

• Tools:– Thermometer

• Other facts/notes– Water freezes at 0 oC– Water boils at 100 oC– Normal room temp is 20 oC– Normal human body temp is 36 oC

Mass Measurement

• Definition: – Mass is the amount of stuff (matter) in an object

• S.I. Unit:– Kilogram (kg)

• Common Units:– Gram (g) 1000 g = 1 kg– Milligram (mg) 1000 mg = 1 g

• Tools:– Triple beam balance

• Other facts/notes– 1 ml of water has a mass of exactly 1 gram– When using a triple beam balance:

• Always “zero” the balance first• Move the largest (100 g) mass first,• Then move the 10 g mass,• Then slide the smallest mass until it balances.• Read balance to nearest .01g