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Even Carnot engine cannot give 100% effi...

Even Carnot engine cannot give `100%` efficiency because we cannot

A

prevent radiation

B

find ideal sources

C

reach absolute zero temperature

D

eliminate friction

Text Solution

Verified by Experts

The correct Answer is:
C
`eta= 1 - (T_(2))/(T_(1)) = 1 implies (T_(2))/(T_(1))= 0 implies T_(2) = 0 "or" T = alpha`
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ALLEN -GEOMETRICAL OPTICS-EXERCISE - 05 (A)
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  2. If mass-energy equivalence is taken into account , when water is coole...

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  3. Even Carnot engine cannot give 100% efficiency because we cannot

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  4. "Heat cannot by itself flow from a body at lower temperature to a body...

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  5. Which of the following parameters does not characterize the thermodyna...

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  6. A Carnot engine takes 3xx10^6 cal of heat from a reservoir at 627^@C a...

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  7. Which of the following statements is correct for any thermodynamic sys...

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  8. Two thermally insulated vessel 1 and 2 are filled with air at temperat...

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  9. Which of the following is incorrect regarding the first law of thermod...

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  10. The temperature -entropy diagram of a reversible engine cycle is given...

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  11. A system goes from A and B via two processes. I and II as shown in fig...

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  12. Two rigid boxes containing different ideal gases are placed on a table...

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  13. The work of 146 kJ is performed in order to compress one kilo mole of ...

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  14. A Carnot engine, having an efficiency of eta=1//10 as heat engine, is ...

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  15. When a system is taken from state i to state f along the path iaf, it ...

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  16. Two moles of helium gas are taken over the cycle ABCDA, as shown in th...

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  17. Two moles of helium gas are taken over the cycle ABCDA, as shown in th...

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  18. Two moles of helium gas are taken over the cycle ABCDA, as shown in th...

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  19. A diatomic ideal gas is used in a Carnot engine as the working substan...

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  20. A thermally insulated vessel contains an ideal gas of molecular mass M...

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