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प्रश्न
In what way does an ‘Ideal machine’ differ from a ‘Practical machine’?
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उत्तर
Ideal machine has 100% efficiency i.e., work done on the machine = work done by the machine.
संबंधित प्रश्न
The moon is revolving around the earth in a circular path. How much work is done by the moon?
The power of a motor is 40 kW. At what speed can the motor raise a load of 20,000 N?
How much energy is gained by a box of mass 20 kg when a man, carrying the box waits for 5 minutes for a bus?
Choose one or more correct alternatives.
For work to be performed, energy must be ______.
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- concentrated
- transformed from one type to another
- destroyed
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(i) P.E. maximum,
(ii) K.E. maximum,
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Fill in the boxe to show the corresponding energy transformation.
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