Question

a closed cylindrical tank of diameter 7 cm and height 4 cm is made from a sheet of metal how much sheet of metal is required

Answer 1

Diameter =cm
Radius =7/2cm
Height =4cm
T. S. A. Of cylinder is = 2pir(r + h)
= 2*22/7*7/2*(7/2+4)
=22(7+8/2)
=22*15/2
=330/2
=165cm
L.S.A. Of cylinder is =2pirh
=2*22/7*7/2*4
=22*4
=88cm


So, area of metal sheet required for L. S. A. Of cylinder is 88cm
And for T. S. A. Of cylinder is 165cm