A variable force F = (3x^2 + 2x) N acts on a particle. The work done by this force in moving the particle from x = 1 m to x = 2 m is: MCQ with Answer and Explanation

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A variable force F = (3x^2 + 2x) N acts on a particle. The work done by this force in moving the particle from x = 1 m to x = 2 m is:

A. 14 J

B. 16 J

C. 12 J

D. 10 J

Answer: Option D

Solution (By JKExamLibrary)

Work done by a variable force is the definite integral of F dx. W = Integral(3x^2 + 2x) dx from 1 to 2. W = [x^3 + x^2] evaluated from 1 to 2. Upper limit: (2^3 + 2^2) = 8 + 4 = 12. Lower limit: (1^3 + 1^2) = 1 + 1 = 2. Work = 12 - 2 = 10 Joules.

This question belongs to: Science Physics

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Correct Answer: Option A

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