Question

a hemispherical depression is cut out from one face of a cubical block of side 7 centimetre such that the diameter of the hemisphere is equal to that of the cube find the surface area of the remaining solid​

Answer 1

SoluTion :-

$\sf {For\ the\ cubical\ block :-}$

$\tt {Edge\ of\ the\ cube, a = 7\ cm}$

$\rule {130}{1}$

$\sf {For\ the\ hemisphere :-}$

$\tt{Diameter\ of\ the\ hemisphere = Length\ of\ the\ side\ of\ the\ cube}$

$\sf {Radius\ of\ the\ hemisphere = \frac{7}{2} }$

Surface area of the remaining solid = Surface area of the cube - Surface area of the circle on one of the faces of the cube + Surface area of the hemisphere.

$\sf {\rightarrow 6a^2 - \pi r^2 + 2 \pi r^2}\\\\\\\sf {\rightarrow 6a^2 + \pi r^2}\\\\\\\sf {\rightarrow 6 \times 7^2 + \frac{22}{7} \times \frac{7}{2} } } \times \frac{7}{2}\\\\\\\sf {\rightarrow 294\ + 38.5\ cm^2}\\\\\\\sf {\rightarrow 332.5\ cm^2}$

$\rule {180}{2}\ Be\ Brainly\ \star$