Question

A solid sphere of diameter 17.5 cm is cut into two equal halves. what will be the increase (in cm2) in the total surface area

Answer 1

Given : Diameter of solid sphere = 17.5 cm
The solid sphere is cut into two equal halves, We will get the 2 hemispheres.

Radius of sphere = 17.5/2 = 8.75 cm

T.S.A of sphere = 4πr²
T.S.A of 2 hemispheres = 2 × 3πr² = 6πr²

Increase in the Total surface area = 6πr² - 4πr² = 2πr²
Increase in the Total surface area = 2πr²

Increase in the Total surface area = 2× (22/7) ×8.75×8.75 = 44 × 1.25 × 8.75
Increase in the Total surface area =481.25 cm².

Hence,the Increase in the Total surface area will be 481.25 cm².

HOPE THIS WILL HELP YOU...

Answer 2

Please refer to the attachment ..

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