Question

If the surface area of a sphere is $144\pi c{m}^2$, then its radius is:

• A. $6cm$
• B. $8cm$
• C. $12cm$
• D. $10cm$

Answer 1

The correct option is A $6cm$

Let radius of sphere be $r$ cm.

We know, surface area of sphere $=4\pi r^2$

$⟹$ $144\pi =4\pi r^2$

$⟹$ $r^2=\frac{144\pi }{4\pi }=36$

$⟹$ $r=\sqrt{36}=6cm$ .

Therefore, option $A$ is correct.