JEE Mains · Physics · STD 11 - Work,energy,power and collision
- JEE Mains 2024
- Hard
- Numerical
A force \(\left(3 x^2+2 x-5\right) N\) displaces a body from \(\mathrm{x}=2 \mathrm{~m}\) to \(\mathrm{x}=4 \mathrm{~m}\). Work done by this force is _______ J.
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(58\)
Step-by-step Solution
Detailed explanation
\(\mathrm{W}=\int_{\mathrm{x}_1}^{\mathrm{x}_2} \mathrm{Fdx}\)
\(\mathrm{W}=\int_2^4\left(3 \mathrm{x}^2+2 \mathrm{x}-5\right) \mathrm{dx}\)
\(\mathrm{W}=\left[\mathrm{x}^3+\mathrm{x}^2-5 \mathrm{x}\right]_2^4\)
\(\mathrm{~W}=[60-2] \mathrm{J}=58 \mathrm{~J}\)
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