Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
If a body has a potential energy of $\left(4 x^2+2 x\right) J$ at a height of $2 \mathrm{~m}$, then the force acting on the body is
PhysicsWork Power EnergyAP EAMCETAP EAMCET 2023 (17 May Shift 2)
Options:
  • A $9 \mathrm{~N}$
  • B $27 \mathrm{~N}$
  • C $18 \mathrm{~N}$
  • D $0 \mathrm{~N}$
Solution:
1307 Upvotes Verified Answer
The correct answer is: $18 \mathrm{~N}$
Potential energy, $U=\left(4 x^2+2 x\right) J$
Force, $\mathrm{F}=\frac{\mathrm{dU}}{\mathrm{dx}}$
$\begin{aligned} & F=\frac{d}{d x}\left(4 x^2+2 x\right)=8 x+2 \\ & \text { at } x=82 m \\ & F=18 N\end{aligned}$
The force acting on the body is $18 \mathrm{~N}$.

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.