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A person holds a bundle of hay over his head for 30 minutes and gets tired. Has he done some work or not ? Justify your answer.

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To determine whether the person holding a bundle of hay over his head for 30 minutes has done any work, we need to analyze the situation based on the definition of work in physics. ### Step-by-Step Solution: 1. **Understanding Work in Physics**: - Work is defined as the product of force and displacement in the direction of the force. Mathematically, it is expressed as: \[ \text{Work} = \text{Force} \times \text{Displacement} \times \cos(\theta) ...
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NCERT ENGLISH-WORK AND ENERGY-Exercise
  1. What is the work done by the force of gravity on a satellite moving ro...

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  2. Can there be displacement of an object in the absence of any force act...

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  3. A person holds a bundle of hay over his head for 30 minutes and gets t...

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  4. An electric heater is rated 1500W. How much energy does it use in 10 ...

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  5. Illustrate the law of conservation of energy by discussing the energy ...

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  6. An object of mass m is moving with a constant velocity upsilon How muc...

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  7. calculate the work required to be done to stop a car of 1500 kg moving...

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  8. In each of the following, a force, F is acting on an object of mass, m...

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  9. Soni says that the acceleration in an object could be zero even when s...

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  10. find the energy in kWh consumed in 10 hours by four devices of power 5...

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  11. A freely falling object eventually stops on reaching the ground. What ...

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  12. A force of 7N acts on an object. The displacement is, say 8m, in the d...

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  13. When do we say that work is done ?

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  14. Write an expression for the work done when a force is acting on an obj...

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  15. Define 1 J of work.

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  16. A pair of bullocks exerts a force of 140 N on a plough. The field bei...

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  17. What is the kinetic energy of an object ?

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  18. Write an expression for kinetic energy of an object.

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  19. The kinetic energy of an object of mass m moving with a velocity of 5 ...

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  20. What is power ?

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