Question

3. A cubical block of side 7 cm is surmounted by a hemisphere. What is the greatest diameter the hemispher can have find the surface area of solid ​

Answer 1

Step-by-step explanation:

The greatest diameter=side of the cube=7cm.

The radius of the hemisphere =3.5cm.

Now,

The Surface Area of Solid=Surface Area of Cube - Surface Area of Base Hemisphere + Curve Surface Area of Hemisphere

Surface Area of Cube

=6×side2

=6×7×7

=294sq cm

Surface Area of Base of Hemisphere is,

=πr2

=722×3.52

=38.5cm2

Curved Surface Area of Hemisphere is,

=2×38.5

=77sq cm

∴ total Surface Area is =294−38.5+77

=332.5sq cm.