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Does the transfer of energy take place w...

Does the transfer of energy take place when you push a huge rock with all your might and fail to move it? Where is the energy you spend going?

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When a force acts on an object, work will be done by that force on the object, if the object undergoes a displacement in the direction of the force. The rock does not move, so there is no transfer of energy. However, one gets tired because the muscular fibres in the body do work due to contraction and relaxation.
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KUMAR PRAKASHAN-WORK AND ENERGY -QUESTION & ANSWER (ANSWER THE FOLLOWING QUESTIONS IN SHORT :)
  1. An object of mass 40kg is raised to a height of 5 m above the ground. ...

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  2. What are the various energy trans-formations that occur when you are ...

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  3. Does the transfer of energy take place when you push a huge rock with ...

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  4. The potential energy of a freely falling object decreases progressivel...

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  5. A battery lights a bulb. Describe the energy changes involved in the p...

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

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

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

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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 hour by 4 devices of power 500 W...

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  11. A certain household has consumed 250 units of energy during a month. H...

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  12. A mass of 10 kg is at a point A on a table. It is moved to a point B. ...

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  13. What is the work done by the force of gravity on a satellite moving ro...

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  14. Think of situation when an obejct gets displaced in the absence of a f...

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  15. An object thrown at a certain angle to the ground moves in a curved pa...

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  16. When is the work done by a force is positive and negative ?

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  17. How is work calculated, if a applying force to the object (i) there is...

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  18. Four men lift a 250 kg box to a height of 1 m and hold it without rais...

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  19. A boy is moving on a straight road against a frictional force of 5 N. ...

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  20. Name different types of energy. Give the unit of energy.

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