Question

A box of weight 100 N is lifted to a height of 10 m above ground. How much potential energy will be stored in the box?

9800 J
1000 J
2000 J
none of the above​

Answer 1

$\large{\underline{\underline{\sf{ \maltese \: {Given:-}}}}}$

• Weight = 100 N
• Height = 10 m

$\large{\underline{\underline{\sf{ \maltese \: {To \: find:-}}}}}$

Potential energy = ?

$\large{\underline{\underline{\sf{ \maltese \: {Solution:-}}}}}$

➊ We know that:–

$\qquad \bull \bf \: {Weight = Mass \times Acceleration }$

$\begin{gathered}\begin{gathered}\qquad \quad {:} \longrightarrow\sf \: {100 = mass \times 10 } \\\end{gathered}\end{gathered}$

$\begin{gathered}\begin{gathered}\qquad \quad {:} \longrightarrow\sf \: { \dfrac{100}{10} = mass } \\\end{gathered}\end{gathered}$

$\begin{gathered}\begin{gathered}\qquad \quad {:} \longrightarrow\sf \: { mass = \cancel\dfrac{100}{10} } \\\end{gathered}\end{gathered}$

$\begin{gathered}\begin{gathered}\qquad \quad {:} \longrightarrow\sf \: \underline{ \boxed {\sf{mass = 10 \: kg }}} \\\end{gathered}\end{gathered}$

➋ We know that:–

$\qquad \bull \bf \: { Potential \: energy=mass \times acceleration \times height}$

$\begin{gathered}\begin{gathered}\qquad \quad {:} \longrightarrow\sf \: {potential \: energy = 10 \times 10 \times 10 } \\\end{gathered}\end{gathered}$

$\begin{gathered}\begin{gathered}\qquad \quad {:} \longrightarrow \underline{ \boxed{\sf \: {potential \: energy = 1000 \: J}}} \\\end{gathered}\end{gathered}$

$\begin{gathered}\begin{gathered}\large \quad \therefore\sf \: { The \: correct \: option \: is \: \underline{\underline{1000 \: J}}} \\\end{gathered}\end{gathered}$

$\large{\underline{\underline{\sf{ \maltese \: {Answer:-}}}}}$

The potential energy is 1000 J.

Answer 2

GiveN :-

• Weight of box = 110 N

• Height = 10 m

• Acceleration due to gravity ( g ) = 9.8 m/s²

To FinD :-

• Total potential energy stored in the box

SolutioN :-

As we know

$\longrightarrow \boxed{ \blue{\bf Weight = mass × acceleration}} \\ \\ \longrightarrow \sf100 = mass \times 9.8 \\ \\ \longrightarrow \sf mass= \frac{100}{9.8}$

Now potential energy of box is

$:\implies \boxed{ \red{ \bf Potential \: Energy = mgh }}\\ \\:\implies \sf P.E = \frac{100}{9.8} \times 9.8 \times 10 \\ \\:\implies \sf P.E =100 \times 10 \\ \\:\implies \boxed{ \green{\sf P =1000 \: j}}$

Potential energy stored in the box is 1000 J