Question

An object of mass $40kg$ is raised to a height of $8m$ above the ground. The gain potential energy by the object: [ Take $g=10m{s}^{-2}$]

• A. $200J$
• B. $3200J$
• C. $1500J$
• D. $1000J$

Answer 1

The correct option is B

$3200J$

Step 1: Given data

Mass, $m=40kg$

Acceleration due to gravity, $g=10m{s}^{-2}$

Height, $h=8m$

Potential energy, $P.E.=?$ ( To be calculated)

Step 2: Calculating the potential energy

$$\begin{gathered} PotentialEnergy(P.E.)=Mass\left(m\right)\times Accelerationduetogravity\left(g\right)\times Height\left(h\right) \\ \Rightarrow P.E.=m\times g\times h \\ \Rightarrow P.E.=40kg\times 10m{s}^{-2}\times 8m \\ \Rightarrow P.E.=3200J \end{gathered}$$

Hence, the correct answer is option (B) i.e. $3200J$