Page 85 - WCS - Electrical

WORKSHOP CALCULATION & SCIENCE - CITS

Volume of prism = Area of base x Height

= 20 x 15
= 300 cm³
Cylinder
1 Find the volume and total surface are of a cylinder having 9cm diameter and 15 cm height.

diameter = 9 cm
radius r = 4.5 cm
height h = 15 cm
Volume V = ?
T.S.A = ?

V = r² h unit ³
22
= x 4.5 x 4.5 x 15
7
= 954.4 cm³

T.S.A = 2 r(h+r) unit²
22
= 2 x x 4.5 (15 + 4.5)
7
22
= 2 x x 4.5 x 19.5
7
= 551.4 cm²
2 Calculate the radius if the curved surface area of a cylindrical roller is 48p cm2 and the roller is 10 cm long
C.S.A = 48 cm²

length = 10 cm
radius = ?
2 rh = 48
2 x x r x 10 = 48
48 x
r =
2 x x 10
= 2.4 cm

3 Find its radius if the volume of a cylinder is 5544 cm3 and its height is 16 cm.
r² h = v
3.14 x r² x 16 = 5544
5544
r² =
3.14 x 16

5544
r² =
50.24
= 110.35

r =
= 10.5 cm

72

CITS : WCS - Electrical - Exercise 6