Question

Express $25\mathrm{m}/\mathrm{s}$ In kmph?

• A. $15\mathrm{Kmph}$
• B. $99\mathrm{Kmph}$
• C. $90\mathrm{Kmph}$
• D. None

Answer 1

The correct option is C

$90\mathrm{Kmph}$

Explanation of the correct answer:

Step 1: Define conversion between m/s to km/hr and state the given data

Conversion between m/s to km/hr:

• To convert a quantity having its unit ‘m/s’ into the unit ‘km/hr, the given quantity should be multiplied by $\frac{18}{5}$.
• For example, $1\mathit{}\mathrm{m}/\mathrm{s}=1\times \frac{18}{5}\mathrm{km}/\mathrm{hr}$

The given quantity is $25\mathrm{m}/\mathrm{s}$.

Step 2: Convert the unit from m/s to km/hr

Since, $1\mathit{}\mathrm{m}/\mathrm{s}=1\times \frac{18}{5}\mathrm{km}/\mathrm{hr}$

Then, $25\mathrm{m}/\mathrm{s}=25\times \frac{18}{5}\mathrm{km}/\mathrm{hr}$

$$\begin{gathered} \Rightarrow 25\mathrm{m}/\mathrm{s}=5\times 18\mathrm{km}/\mathrm{hr} \\ \Rightarrow 25\mathrm{m}/\mathrm{s}=90\mathrm{km}/\mathrm{hr} \end{gathered}$$

Hence, option (C) is the correct option.