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P. 80
WORKSHOP CALCULATION & SCIENCE - CITS
EXERCISE 6: Mensuration 3D
Mensuration - Surface area and volume of solids - cube,
cuboid, cylinder, sphere and hollow cylinder
Cube
All sides of cube are same i.e length,breadth and height have same value. It is bounded by six equal square faces.
Volume of cube = side x side x side
= a³ unit³
Lateral surface area = 4a² unit²
Total surface area = 6 x side x side
= 6a² unit² = 1.732
Diagonal d = a
Rectangular solid (or) cuboid
Rectangular soild is bounded by six rectangular surfaces and opposite surfaces are equal and parallel to each
other.
Volume of rectangular solid
= Length x breadth x height
= l . b . h unit³
Lateral surface area = 2h(l+b) unit²
Total surface area = 2lb + 2bh + 2hl
= 2(lb+bh+hl) unit²
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