AMBASSADOR SCHOOL
DUBAI
Grade VI: Measurement
[Length, Area, Volume and Mass]
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Measurement is need to measure things with accuracy and speed.
Measurement is comparing unknown quantity with known standard quantity of same nature.
Measurement consist of Numerical value X unit eg. Mass of object is 20kg , 20 is numerical
value and kg is unit.
Fundamental quantity: Quantity which does not depend on any other quantity is called
fundamental quantity.
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Derived quantity:
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System of units:
F P S system
M K S system
C G S system
Length
Foot
Meter
Centimeter
mass
Pound
Kilogram
Gram
time
Second
Second
second
1. MEASURING LENGTH:
 Parallax error
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SI unit (MKS system) of length is meter
In CGS system unit for length is centimeter
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Multiples and submultiples of meter:
10mm = 1cm
1mm= 1/10cm
100cm = 1m
1cm= 1/100 m
1000m = 1km
1m= 1/1000km
Smaller distances are measured in mm, cm
Larger distances are measured in meter kilometer.
Instrument used for measurement
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Least count of instrument: Smallest measurement that can be measured accurately by the
instrument is called least count
Least count of meter scale: 1mm
Least count of vernier calipers : 0.1mm
Least count of screw gauge: 0.01mm
Measuring the length of curved line:
TO FIND THICKNESS OF COIN BY CENTIMETER SCALE.
Procedure: To find accurate thickness of a coin, take say 5 coins, place them one upon another .
Measure the thickness of 5 coins. Divide the total by 5. It will give accurate thickness of coin
To find diameter of wire using centimeter scale.
Procedure: To find the diameter of thin wire wind the wire over a smooth pencil in the form of thin coil
such that there are say 10 turns. If the length of wire is say 5mm, then the diameter of wire is
Diameter= length of the coil / No of turns in the coil.
= 5/10
= The diameter of wire is 0.5mm
To find length of curved line.
Place a thread along the curve. Care should be taken that thread is neither too tight or not too loose
when moved along the curved line. Remove the thread from the curve and place it straight along the
meter scale. The length of thread is equal to the length of curved line.
To find Diameter of Spherical object:
Place a wooden blocks on either side of the ball. The distance between the inner edges of the two block
will give the diameter of ball.
To find length of curved surface.
Procedure: Wrap the string round the curve surface. Spread the string on a meter scale such that its not
too tight or too loose. The length measured will give the length of curved surface.
2. MEASURING AREA
 Space occupied by an object is called AREA.
 Unit of area: SI system - m2
CGS system- cm2
Conversion of m2 to c m2
m2= m x m
= 100cm x 100 cm
= 10000 cm2
= 104 cm2
: to convert from m2 to cm2 multiply by 104
Eg: 1. Convert 2 m2 to cm2
= 2 x 104 cm2
2. Convert 6 m2 to cm2
= 6 x 104 cm2
Conversion of cm2 to m2
cm2= cm x cm
= 1/ 100m x 1/100 m
= 1/10000 m2
= 10- 4 m2
: to convert from cm2 to m2 multiply by 10- 4
Eg: 1. Convert 4 cm2 to m2
= 4 x 10- 4 cm2
2. Convert 6 cm2 to m2
= 6 x 10- 4 cm2
Area of regular shapes:
Area of irregular objects: Area of irregular objects can be found by using graph paper.
Procedure: Trace the outline of object on the graph. Mark and count the full square. Also count the
numbers of square which have half or more than half within the outline. Add them to get total no of
squares. Since in graph 1 square is 1cm2 , we can calculate the area within outline.
3. MEASURING VOLUME:
 Amount of space that an object fills is called Volume
 Unit of area: SI system - m3
CGS system- cm3
Conversion of m3 to c m3
m3= m x m x m
= 100cm x 100 cm x 100cm
= 1000000 cm3
= 106 cm3
: to convert from m3 to cm3 multiply by 106
Eg: 1. Convert 2 m3 to cm3
= 2 x 106 cm2
2. Convert 6 m3 to cm3
= 6 x 106 cm3
Conversion of cm3 to m3
Cm3= cm x cm x cm
= 1/ 100m x 1/100 m x 1/100 m
= 1/1000000 m3
= 10- 6 cm3
: to convert from cm3 to m3 multiply by 10- 6
Eg: 1. Convert 4 cm3 to m3
= 4 x 10- 6 cm3
2. Convert 6 cm3 to m3
= 6 x 10- 6 cm3
Measuring volume of regular objects:
Measuring volume of liquid:
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1ml = 1cm3
1 litre = 1000ml
1litre = 1000cm3
1m3= 1000litre.
Measuring volume of irregular objects:
4. MEASURING MASS:
 Mass is defined as the amount of matter contained in a substances.
 SI unit of mass is Kg
 CGS unit of mass is gm
Conversion of unit of mass:
 1kg = 1000gm
 1 gram = 1000mg
 1 quintal = 100kg
 1 tonne = 1000 g
Instrument used to measure mass: