Topic: Measurements and Density

Time Rate at which something

happens Instruments: Stop watch, clock Units: seconds, minutes, hour,

days

Length Distance between two points Instruments: Ruler, Meter Stick Units: feet, miles, meter,

kilometer

5,280 feet = 1 mile = 1.6 kilometer

Metric System

Kilometer

DecameterMeter

DecimeterCentimeter

Millimeter

Hectometer

Based on a Factor of 10

Reading a metric ruler correctly:This point can be read as 6.70 cm. or 67.0 mm.

More Practice!

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Temperature Average kinetic energy in a sample

Instruments: thermometer Units: °F, °C, ˚K ESRT pg 13

Mass Amount of matter in an object Instruments: Electronic Scale Units: grams

Mass vs. Weight

Mass - amount of molecules in an object.

Weight - effect of gravity on mass

Think of Astronauts

The Moon’s gravity is 1/6th of the Earth’s If you weight 130 pounds on Earth, on the Moon you would

weigh 21.7 lbs. Space suit worn by astronauts weighed 180 pounds on Earth

and 30 pounds on the Moon with the reduced lunar gravity.

Volume Amount of space something takes up Instruments: graduated cylinder,

ruler Units: ml, cm3

V = LxWxH

Measuring Volume Width

HeightLength

Measuring Volume

Just Right

Practice

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Water Water DisplacemeDisplacement Methodnt Method

MeniscusMeniscus

How do you measure volume for an irregular object?

Measuring Volume

Always read the meniscusHow do we measure volume of a irregular object?

Volume with object

Original Volume

When Stating a Measurement Remember the…

cm 0C

cm3

ml

sec. g

FQ What is the volume of this

rock?

Topic: Density changes with Temperature & Pressure

Density

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ESRT pg 1 - Density = mass/volume

Units = g/cm3 or g/ml

Density Triangle

Phases Of Matter

Phases of Matter In most cases

Solids are - Liquids are - Gases are -

The exception is water because -

When volume is constant (same)…

Mass decreases, -

Mass increases, -

Question

If a uniform substance has a mass of 18 g, volume 6 cm3. If cut exactly in half,

what happens to the density?

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As temperature increases, -

When mass is constant (same)…

Volume decreases (compacts), atoms are closer together

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Volume increases (expands), atoms are farther apart,

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Heater

Warm air

Lower Density

Air Rises

Air cools

Density Increases

Air sinks

Convection – -

Pressure

Pressure -

Pressure increases, volume decreases,

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Pressure decreases, volume increases

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Lets test it !!!!