The Metric System

How do we measure things in science?

Length (measures the distance from one

point to another)

•Base Unit–Meter

• Tool–Meter stick/ruler

Meter sticks

This lizard is 3 meters long!(a meter is about 39 inches)

Volume(measures the amount of space an

object takes up )

• Base Unit–Liter• (liquids)

–Cubic centimeters• (solids)

• Tool–Graduated

Cylinder (liquids)–Ruler (solids)

Graduated CylindersMeasure the volume of liquids

Three steps to reading a graduated cylinder

1. Place the graduated cylinder on level surface

2. Read at eye level3. Read from the bottom of the

meniscus

Formula for finding the volume of a rectangular solid

Length x Width x Height L x W x H

Finding the volume of an irregular object

1. Place enough water in a graduated cylinder to cover the object. Record the volume.

2. Add the object and record the new volume.

3. Find the difference between the two volumes and that is the volume of the irregular object.

Mass (measures the amount of matter in

an object)

•Base Unit–gram

• Tool–Electric balance

Electronic balance used to measure mass

Steps before using a balance

1.Clean the weigh pan2.Tare the balance (zero it

out)

Temperature(measures heat and chill)

•Base Unit–Degrees

celcius

• Tool–Thermometer

This man is in a freezing cold environment as can be seen by his frozen hair and beard. He is sitting in a natural hot spring that is very warm at the same time!

Density

• How closely the molecules of an object are packed together.

• Density can be calculated if the mass and volume are known

• Density = mass divided by volume

Less dense liquidsfloat on more dense liquids in this density column

Weight of an object

• The mass of an object multiplied by the force of gravity.• Weight changes if gravity changes.

(like on the moon)• Mass does not change on the moon.• Weight is the effect of the force of

gravity on an object.

Your weight will be less on the moon, but your mass does not

change