Question

Avinash can run with a speed of $8\mathrm{m}{\mathrm{s}}^{-1}$ against the frictional force of $10\mathrm{N}$, and Kapil can move with a speed of $3\mathrm{m}{\mathrm{s}}^{-1}$ against the frictional force of $25\mathrm{N}$. Who is more powerful and why?

Answer 1

Step 1: Given information

Avinash, $$\begin{gathered} \mathrm{Speed}=8\mathrm{m}{\mathrm{s}}^{-1} \\ \mathrm{Frictional}\mathrm{force}=10\mathrm{N} \end{gathered}$$

Kapil, $$\begin{gathered} \mathrm{Speed}=3\mathrm{m}{\mathrm{s}}^{-1} \\ \mathrm{Frictional}\mathrm{force}=25\mathrm{N} \end{gathered}$$

Step 2: To find- Who is more powerful, Kapil or Avinash?

Finding who is more powerful

We know the formula,

$$\begin{gathered} \mathrm{Power}=\mathrm{Force}\times \mathrm{velocity} \\ \mathrm{P}=\mathrm{F}\times \mathrm{v} \end{gathered}$$

Power delivered by Avinash will be:

$$\begin{gathered} \mathrm{P}=\mathrm{F}\times \mathrm{v} \\ =10\times 8 \\ =80\mathrm{W} \end{gathered}$$

Power delivered by Kapil will be:

$$\begin{gathered} \mathrm{P}=\mathrm{F}\times \mathrm{v} \\ =25\times 3 \\ =75\mathrm{W} \end{gathered}$$

Therefore, Avinash is more powerful because he delivers a power of $80\mathrm{W}$, while Kapil delivers a power of $75\mathrm{W}$.