Question

Calculate the volume of a sphere with radius 2m. $\left( \pi =3.142 \right)$
A. $33.51{{m}^{3}}$
B. $73.51{{m}^{3}}$
C. $63.51{{m}^{3}}$
D. None of these

Answer 1

Hint:We will first start by using the fact that the volume of a sphere with radius r is $\dfrac{4}{3}\pi {{r}^{3}}$. Then we will use the value of $\pi =3.142$ given to further simplify the solution and find the value of the volume of the sphere.

Complete step-by-step answer:
Now, before starting the solution we first start by understanding that the volume of a circle with radius r is $\dfrac{4}{3}\pi {{r}^{3}}$.

Now, we have the sphere whose radius is 2m. So, we have its volume as,
$\begin{align}
  & =\dfrac{4}{3}\pi {{r}^{3}} \\
 & =\dfrac{4}{3}\pi r{{\left( 2 \right)}^{3}} \\
 & =\dfrac{4}{3}\pi \left( 8 \right) \\
 & =\dfrac{32}{3}\pi \\
\end{align}$
Now, we have to substitute $\pi =3.142$. So, we have,
$\begin{align}
  & volume=\dfrac{32}{3}\times 3.142{{m}^{3}} \\
 & =33.51{{m}^{3}} \\
\end{align}$
Hence, the correct option is (A).

Note: It is important to note that to solve this question one must know that the formula for finding the volume of a sphere with radius r is $\dfrac{4}{3}\pi {{r}^{3}}$. Also, one must remember that the formula for finding total surface are of a sphere is $4\pi {{r}^{2}}$.