A force of 31i^+2j^ +4k^ N gives displacement of 10j^ m. The work done is
Correct answer: D. zero
- A. 20 J
- B. 26 J
- C. 32 J
- D. zero
Explanation
Work done (W) is given by the dot product of force (F) and displacement (d). If the force and displacement vectors are perpendicular (as given in the problem), their dot product is zero, implying no work is done.Incorrect Options Explanation:(a) 20 J: This would be the work done if the force and displacement vectors were parallel.(b) 26 J: This value doesn't correspond to the scenario described in the question.(c) 32 J: This value doesn't correspond to the scenario described in the question.
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About Work and Energy
Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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