Question

.A hemispherical tank is made up of an iron sheet 1 cm thick. If the inner radius is 1 m, then find the volume of the iron used to make the tank.​

Answer 1

volume of inner 2by 3 π r power 3

$volume = 2 \div 3 \times 22 \div 7 \times 1 \times 1 \times 1 \\ \\ \\ \\ 2.093m { }^{3} \\ \\ \\ \\ now \: outer \: radius = 1 + 0.01 \\ = 1.01m \\ \\ volume \: of \: \: outer \: = 2 \div 3\pi \: r {}^{3 } \\ \\ \\ \\ v = 2 \div 3 \times 22 \div 7 \div 1.01 \times 1.01 \times 1.01 \\ \\ \\ \\ 2.158m {}^{3} \\ \\ \\ now \: \: area \: of \: sheet \: 2.158 - 2.093 \\ = 0.0657approx \: m \: {}^{3} \\ \\ and \: 6.57cm {}^{3}$