AIM: How is the volume of irregularly shaped objects measured?€¦ · AIM: How is the volume of...

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AIM: How is the volume ofirregularly shaped objects measured?

VOCABULARY

Irregular shaped object Meniscus Increment Graduated Cylinder Overflow Can

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OBJECTIVE

To successfully and accuratelyread the level in a graduated

cylinder andmeasure the volume of

irregularly shaped objects.

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DEFINITION

What is volume ?

Volume is the amount ofspace that matter (a solid, a

liquid or a gas) takes up.

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In the Metric System

For liquids, the standard(base) unit of measure for

volume is the…

Liter

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Basic Terminology

1 liter = 1000 milliliters

1 L = 1000 mL

Remember…a milliliter takes upthe SAME AMOUNT OF SPACE

as a cubic centimeter (cm3)

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Metric Tool for Measuring Volume

Graduated Cylinder

In order to accurately use agraduated cylinder, there are a

few important things toremember!!!

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What is the Meniscus?

You have to readthe level of thewater at themeniscus

What is ameniscus?

A curve or blur inthe water level

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Why do you thinkits important toread the meniscusat eye level?

To obtain anaccurate reading

What is the Meniscus?

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Why should we keepthe GraduatedCylinder as flat aspossible duringreading?

To make sure thatthe level is even andthe liquid level isaccurate

What is the Meniscus?

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Lets Practice reading a graduatedcylinder: The increment

could beDIFFERENT on

each cylinder

Sometimes theincrement is 1mL,other times its 5mLor even 0.5mL or

0.1 mL!You have to check!

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Lets Practice reading a graduatedcylinder:

What is theincrement ofthis cylinder?

What is thevolume?Bottom of meniscus

Top of meniscus

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Lets Practice reading a graduatedcylinder:

What’s theincrementof thiscylinder?

What is thevolume?

6

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Lets Practice reading a graduatedcylinder:

What’s theincrement ofthis cylinder?

What is thevolume?

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Lets Practice reading a graduatedcylinder:

What’s theincrement ofthis cylinder?

What is thevolume?

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Lets Practice reading a graduatedcylinder:

What’s theincrement ofthis cylinder?

What is thevolume?

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What is this called?

A rock

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How can you measure its volume?

Can youmeasure itsheight, width,and length witha ruler?

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So how do you measure its volume?

Waterdisplacement

method

You’ll need agraduated

cylinder or anoverflow can

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Water Displacement Method

Using yourgraduatedcylinder

Step 1: measurethe volume ofwater

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Water Displacement Method

Step 2: insertthe rock in thewater

Re-measure thewater in thecylinder!

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Water Displacement Method

Step 3: Subtractthe firstmeasurementfrom thesecond.

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Water Displacement Method

The differencein themeasurementsis the volume ofthe rock in mL

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Water Displacement Method

…and since weknow that1mL = 1cm3,

we know thevolume of thesolid object in 2units!!!