Hg
Name: Class 9 STICK TO YOUR WALL IN STUDY AREA
___________________________________________________________________________________________________________________________________
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The Hg Classes (8
th
to 12
th
) By: Er Hershit Goyal (B.Tech. IIT BHU), 134-SF, Woodstock Floors, Nirvana Country, Sector 50, GURUGRAM +91 9599697178.
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Mensuration Formulae (3D shapes)
Shape
Surface Area (cm
2
or m
2
)
Volume (cm
3
or m
3
or Litres)
CUBOID
LSA or Area of 4 walls = 2h (l + b)
TSA = 2 (lb + bh + hl)
V = l b h
l = length, b = breadth h = height
CUBE
LSA or Area of 4 walls = 4a
2
TSA = 6a
2
V = a
3
a = length of a side of the cube
RIGHT CIRCULAR
CYLINDER
CSA = 2 πrh
TSA = 2πr (h + r)
V = πr
2
h
r = radius of base,
h = height
RIGHT CIRCULAR CONE
CSA = πrl
TSA = πr (l + r)
l
2
= r
2
+ h
2
V =
𝟏
𝟑
πr
2
h
r = radius of base,
h = height,
l = slant height
SPHERE
TSA = CSA = 4πr
2
V =
𝟒
𝟑
πr
3
r = radius
HEMI-SPHERE
CSA = 2πr
2
TSA = 3πr
2
V =
𝟐
𝟑
πr
3
1 m = 100 cm
1 km = 1000 m
1 m
2
= 100 x 100 cm
2
= 10
4
cm
2
1 m
3
= 100 x 100 x 100 cm
3
= 10
6
cm
3
1 m
3
= 1000 L = 1 Kilo litres
1 L = 1000 cm
3
or 1000 c.c.
