Question

Is the radius of sphere is doubled how much increased is done in curved surface area

Answer 1

Let the radius be =r

So,curved surface will be

▶$4 \times π \times {r}^{2}$ - (1)

Given ,

The radius is increased by 2 times,

So radius becames= 2r

Now new curved surface area will be =

▶$4 \times π \times {2r}^{2}$ -(2)

On dividing (1) by (2) ,

$\frac{csa 1}{csa 2} =\frac{4 \times π {r}^{2}}{4 \times π {2r}^{2}}$

$\frac{csa 1}{csa 2} =\frac{\cancel{4} \times \cancel{π} \times {r}^{2}}{\cancel{4} \times \cancel{π} \times {2r}^{2}}$

$\frac{csa 1}{csa 2} =\frac{{r}^{2}}{{2r}^{2}}$

$\frac{csa 1}{csa 2} =\frac{\cancel{{r}^{2}}}{2 \times \cancel{{r}^{2}}}$

We get,

$\frac{csa 1}{csa 2} =\frac{1}{2}$

The new curved surface area will be 2 times the original one.

Answer 2

Heya...

Here's your answer.........

Let the radius be r

Now the surface area = 4π(r) ² = 4πr²

The radius of the sphere is doubled.

The radius = 2r.

Now the surface area = 4π(2r)² = 16πr² .

Increase % in area = 16πr²-4πr²/4πr² * 100 = 12/4*100 = 300% .

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✨✨✨✨BY BeWaFa ✨✨✨

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Thanks...!!!

XD

Sorry baby 'wink'