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NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

1 Hard

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Application +4 | -1

A variable force, given by the 2-dimensional vector

\vec F = \left( {3{x^2}\hat i + 4\;\hat j} \right)

, acts on a particle. The force is in newton and x is in metre. What is the change in the kinetic energy of the particle as it moves from the point with coordinates (2,3) to (3,0) (The coordinates are in metres)

View answer and explanation

Correct option: C

+ 7\,J

Option C (

+ 7\,J

) is correct because the work done by the variable force, which equals the change in kinetic energy, is calculated by integrating the force over the given displacement.

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