Page 86 - WCS - Electrical

WORKSHOP CALCULATION & SCIENCE - CITS

4 Find the diameter of the tank if the volume of a circular tank is 68.46 m3, its height is 2 m.

r² h = 68.46
68.46
r² =
3.14x2
r² = 10.9
r =

= 3.3 m
diameter = 2r
= 2 x 3.3
= 6.6 m
5 A cylindrical vessel is to be made of 3 metre long and 1.9994 metre diameter. Calculate its surface area, if it
is in a closed form on one end.
h = 3m
d = 1.9994 m
r = 0.9997 m

T.S.A = C.S.A + Base area
= 2 rh + r²
22 22
= (2 x x 0.9997 x 3) + ( x 0.99997²)
7 7
= 18.85 + 3.14
= 21.99 m²

6 How many litres of water a cylinder of radius 75 cm and height 100 cm can hold.
V = pr² h unit³
= 3.142 x 75 x 75 x 100
= 1767375 cm3

1767375
= [1000 cc = 1 litre]
1000

= 1767.375 litres.
7 Calculate the height of cylindrical tin if a closed rectangular box 40 cm long, 30 cm wide and 25 cm deep has
the same volume as that of cylinder tin of radius 17.5 cm.

Volume of cylinder = Volume of rectangular box
r² h = l x b x h
22
x 17.5 x 17.5 x h = 40 x 30 x 25
7
h =
=
= 31.17 cm

8 An oxygen cylinder is 15 cm in diameter and 100 cm in length. It is filled with gas under pressure so that every
cm³ of the cylinder contains 120 cm³ of gas. How much cc of oxygen does this hold?
Volume of cylinder = r² h unit³

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CITS : WCS - Electrical - Exercise 6