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.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
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.
Practise Work and Energy
750 free Work and Energy MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Work and Energy questions
A body moves a distance of 10 m along a straight line under the action of a force of 5 newton if the work done is 25 joules, the angle which the force takes with the direction of motion of the body is
38. Solar energy conversion cell: (Work, Power & Energy, renewable energy resources)
Question 28: When two protons are brought close together, what happens to their potential energy? (Work, Power & Energy, interconversion of potential and kinetic energy)
A body travels a displacement of 10 m by a force of 5 N. If the work done is 25 J, then the angle between F and displacement is
When a person lifts a body from the ground, the work done by the lifting force is
A bomb at rest explodes into two pieces of the same mass. The two pieces will