2. A show-piece shown in figure 14.10 is made of twosolids a cube and

1.	2. A show-piece shown in figure 14.10 is made of twosolids a cube and a hemisphere. The base of the blockis a cube with edge 7 cm and the hemisphere fixed onthe top has diameter 5.2 cm. Find the total surfacearea of the piece.cmFigure 14.10
Answer» Given ;Side of a cube = a = 7cmRadius of a hemisphere = 5.2/2 = 2.6 cm = Total surface area of a solid= L.S.A of cube + Bottom side area + C.S.A of hemisphere= 4a^2 + a^2 + 2πr^2= 5a^2 + 2πr^2 = (5×7×7) + 2×(22/7)×2.6×2.6= 245 + 42.49= 287.49 sq. cm

2. A show-piece shown in figure 14.10 is made of twosolids a cube and a hemisphere. The base of the blockis a cube with edge 7 cm and the hemisphere fixed onthe top has diameter 5.2 cm. Find the total surfacearea of the piece.cmFigure 14.10

Answer»

Given ;Side of a cube = a = 7cmRadius of a hemisphere = 5.2/2 = 2.6 cm

= Total surface area of a solid= L.S.A of cube + Bottom side area + C.S.A of hemisphere= 4a^2 + a^2 + 2πr^2= 5a^2 + 2πr^2

= (5×7×7) + 2×(22/7)×2.6×2.6= 245 + 42.49= 287.49 sq. cm