Measuring Volume

advertisement
Measuring Volume
What is Volume?
• Volume is the amount of space an object takes
up.
• Volume can be used to directly measure liquids
usually with a beaker or graduated cylinder, or
with a formula to measure the volume of solids.
• Formula for measuring volume in solids:
• V=LxWxH
Metric Units of Volume Measurement
Liquids
• Liter (L) – Unit of measurement (starting point)
• Milliliter (ml) – (1 thousandth of a liter, 0.001, 10-3)
• Centiliter (cl) – (1 hundredth of a liter, 0.01, 10-2)
• Deciliter (dl) – (1 tenth of a liter, 0.1, 10-1)
• Decaliter (dal) – (ten liters, 10, 101)
• Hectoliter (hl) – (1 hundred liters, 100, 102)
• Kiloliter(kl) – (1 thousand liters, 1000, 103)
Solids
• Cubic centimeters (cc, cm³)
Volume of irregular shaped solid
objects
• Irregular shaped objects can be measured by:
– Putting the object in water and measuring the
amount of water displaced.
– Finding the difference between the volume of
water and the total volume of the water and the
object.
• The units deciliter, decaliter and hectoliter are
not used as much as the other units.
• liters are used to measure the capacity of
larger things such as pitchers and aquariums
• Kiloliters are used to measure the capacity
of even larger things like swimming pools.
Metric Conversions
• To convert larger units to smaller ones , you MULTIPLY by units of 10
• To convert smaller units to larger ones you DIVIDE by units of 10
– Example:
1000
100
10
1
0.1
0.01
0.001
kiloliter
hectoliter
decaliter
Unit
(Liter)
deciliter
centiliter
milliliter
– To convert 8 Liters to centiliters (1 hundredth of a liter), you multiply by
100:
• 8 x 100 = 800 cL (8 liters = 800 centiliters)
– To convert 6 milliliters (1 thousandth of a liter) to liters, you divide by 1000
• 6 ÷ 1000 = 0.006 L (6 milliliters = 0.006 L)
OR
• Find out how far apart the two prefixes are on the line
above. For example, kilo and hecto are one place apart,
kilo and deka are two places apart, etc.
• Move the decimal point to the left to convert smaller
units or right to convert larger units by the number of
places you found in the previous step. If there is no
decimal in the number, assume it's after the last digit in
the number.
1000
kiloliter
100
hectoliter
10
decaliter
1
Units
(liters)
0.1
deciliter
0.01
Centiliter
0.001
milliliter
Example #1
• To convert 1 kiloliter to liters (convert larger to
smaller), move the decimal 1 place to the RIGHT and
add zeros where needed for the number of places
you move down the table.
Decimal Point
Start
1
kiloliter
0
hectoliter
0
decaliter
• 1 kiloliter = 1000 liters
End
0
liter
deciliter
Centiliter
milliliter
Example #2
• To convert 1 milliliters to liters (convert smaller to
larger), move the decimal 1 place to the LEFT and
add zeros where needed for the number of places
you move down the table.
Decimal Point
End
kiloliter
hectoliter
decaliter
• 1 milliliter = 0.001 liters
liter
0
deciliter
0
Centiliter
Start
1
milliliter
Convert the following measurements
• 12 liters to centiliters
1200 cl
________
• 3 kiloliters to liters
3000 L
_________
• 22 liters to milliliters
22000 ml
_________
• 5 centiliters to liters
0.05 L
_________
• 8 deciliters to liters
0.8 L
_________
• 7 milliliters to deciliters
0.07 dl
_________
How to Measure Volume
We will be using graduated cylinders to
find the volume of liquids and other objects.
Read the measurement based on the bottom of the
meniscus or curve. When using a real cylinder, make
sure you are eye-level with the level of the water.
What is the volume of water in this cylinder? _____mL
43
What causes the meniscus?
A concave meniscus occurs when the molecules of the
liquid attract those of the container. The glass attracts
the water on the sides.
What is the volume of water in each cylinder in milliliters?
NOTE: Pay attention to the scales for each cylinder.
37 ml
52 ml
22.5 ml
Images created at http://www.standards.dfes.gov.uk/primaryframework/downloads/SWF/measuring_cylinder.swf
Measuring Liquid Volume
Measuring Solid Volume
9 cm
We can measure the volume of regular object
using the formula length x width x height.
8 cm
10 X _____
8 X _____
9 = ________
720 cm³
_____
10 cm
We can measure the volume of
irregular object using water displacement.
ml
Amount of H2O with object = 260
______
ml
About of H2O without object = 200
______
Difference = Volume = ______
60 ml
Using the beaker of water on your desk, measure out the
following volumes in the graduated cylinder.
(pour the water back into the beaker after each
measurement).
•
•
•
•
•
•
20 ml
50 ml
6 ml
100 ml
13 ml
27 ml
Find the volume of the following solid
objects on your desk.
(Tilt the cylinder and slide any solid object gently into
it. DO NOT drop the object directly into the cylinder!)
• Rock __________
• Small density cube __________
• Marble __________
• Paperclip __________
Download