Question

A boy pulls up a bucket of water from a well $80m$ deep. If the mass of the bucket, along with water is $20kg$, calculate the amount of work done by the boy. [Take $g=10m/s^2$]

Answer 1

Step 1: Given data

Mass of bucket with water, $m=20kg$

Depth of well i.e. vertical height, $s=80m$

Acceleration due to gravity, $g=10m/s^2$

Work done, $W=?$ (To be calculated)

Step 2: Calculating the force required to lift the water

Applying, $F=m\times g$

By putting the given values in a formula, we get

$$\begin{gathered} F=20kg\times 10m/s^2 \\ \therefore F=200N \end{gathered}$$

Step 3: Calculating the work done

Applying, $Workdone\left(W\right)=force\left(F\right)\times displacement\left(s\right)$

By putting the given values in a formula, we get

$$\begin{gathered} W=F\times s \\ W=200N\times 80m \\ \therefore W=16,000J \end{gathered}$$

Hence, work done by the boy is $16,000J$