Question

A vessel is in the form of a hemisphere mounted on a hollow cylinder. The diameter of the hemisphere is 21 cm and the height of vessel is 25 cm. If the vessel is to be painted at the rate of Rs.3.5 per cm ², then find the total cost to paint the vessel from outside.

Answer 1

Total surface area of vessel(T) = S+U

where, S is surface area of hemisphere

and U is the surface area of cylinder

Hence, S = $2\pi r^{2}$

and U = $2\pi rh$

where, r is radius which is half of diameter = 10.5 cm

and h is height = 25 cm

So, T = 2342.057 $cm^{2}$

hence, total cost is = 3.5*T = Rs. 8197.20

Answer 2

ANSWER :

Total cost of painting the vessel from outside is ₹ 8200.50

SOLUTION IS IN THE ATTACHMENT.

HEMISPHERE:

A plane passing through the centre cuts the sphere in two equal parts each part is called a hemisphere.

Curved surface area of hemisphere = 2πr²

CYLINDER:

Cylinder is a solid figure obtained by revolving the rectangle about its one side.

Curved surface area of cylinder = 2πrh

HOPE THIS ANSWER WILL HELP YOU…