11) Work done by a variable force is determined by dividing: (Work, Power & Energy, Work Done by Constant Force and Variable forces)
Correct answer: C. both force and displacement into small intervals
- A. force into small intervals
- B. displacement into small intervals
- C. both force and displacement into small intervals
- D. force into small and displacement into large intervals
Explanation
Explanation: To calculate the work done by a variable force over a finite distance, we need to account for the changes in both force and displacement along the path. Dividing only force or only displacement wouldn't provide a complete picture of the work done. By dividing both into small intervals and summing the work done in each interval, we can obtain an accurate estimate of the total work. Incorrect Options:(a) While dividing force into small intervals helps in approximating variable forces, it doesn't account for the variation in displacement, which is essential for calculating work.(b) This method only considers the path taken, but it doesn't take into account the varying force applied at different points. This leads to an incomplete picture of the work done.(d) This approach is inconsistent and doesn't provide a reliable way to calculate work done by a variable force.
Last updated
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
748 free Work and Energy MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.