(A) The formula for the surface area of a sphere is $A = 4 \pi r^2$.Given that $A = 7850 \, cm^2$ and $\pi = 3.14$,we substitute these values into the

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(A) The formula for the surface area of a sphere is $A = 4 \pi r^2$.Given that $A = 7850 \, cm^2$ and $\pi = 3.14$,we substitute these values into the formula:$7850 = 4 \times 3.14 \times r^2$$7850 = 12.56 \times r^2$$r^2 = \frac{7850}{12.56}$$r^2 = 625$$r = \sqrt{625} = 25 \, cm$.Therefore,the radius of the sphere is $25 \, cm$.

Class 9 Mathematics Surface Areas and Volumes Surface Area of a Sphere

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The surface area of a sphere is $7850 \, cm^2$. Find its radius in $cm$. (Use $\pi = 3.14$)

A
$25$
B
$35$
C
$50$
D
$45.5$

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Surface Areas and Volumes

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Surface Area of a Sphere

Find the curved surface area and the total surface area of a hemisphere with a radius of $14\, cm$.

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The diameter of a sphere is decreased by $25\%$. By what per cent does its curved surface area decrease (in $\%$)?

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Find the radius of a sphere whose surface area is $154 \, cm^2$. (in $, cm$)

Medium

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The surface area of a sphere and the curved surface area of a hemisphere are equal. Find the ratio of their radii.

Medium

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Find the surface area of a sphere of radius $30 \, cm$ $(\pi = 3.14)$ (in $cm^2$).

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The surface area of a sphere is $7850 \, cm^2$. Find its radius in $cm$. (Use $\pi = 3.14$)

Similar Questions

Find the curved surface area and the total surface area of a hemisphere with a radius of $14\, cm$.

The diameter of a sphere is decreased by $25\%$. By what per cent does its curved surface area decrease (in $\%$)?

Find the radius of a sphere whose surface area is $154 \, cm^2$. (in $, cm$)

The surface area of a sphere and the curved surface area of a hemisphere are equal. Find the ratio of their radii.

Find the surface area of a sphere of radius $30 \, cm$ $(\pi = 3.14)$ (in $cm^2$).

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