A gardener pushes a lawn roller through a distance $20 \mathrm{~m}$. If he applies a force of $30…
- $3640 \mathrm{~J}$
- $2460 \mathrm{~J}$
- $3940 \mathrm{~J}$
- $2940 \mathrm{~J}$
Solution
$\begin{aligned} & \mathrm{W}=\mathrm{F} \Delta \mathrm{S} \cos (\theta) \\ & \mathrm{W}=\overrightarrow{\mathrm{F}} \cdot \overrightarrow{\Delta \mathrm{S}}=\mathrm{F} \Delta \mathrm{S} \cos 60^{\circ}=30 \times(9.8) 20 \times \frac{1}{2}=2940 \mathrm{~J}\end{aligned}$Asked in: MHT CET 2022 (05 Aug Shift 2)