Question

If every side of a cube of volume $V$ is doubled then its volume becomes $kV$. The value of $k$ is equal to:

• A. $8$
• B. $4$
• C. $2$
• D. $16$

Answer 1

The correct option is A $8$

Let the side of cube is $a$ cm.

Then, volume of cube $V=a^{3}c{m}^3$.

If side is doubled, then side $=2a$.

Then, volume of new cube $=kV=$ $(2a{)}^3=8a^{3}c{m}^3$.

$\therefore kV=8V\Rightarrow k=8$.

Hence, option $A$ is correct.