Home
Class 12
PHYSICS
Assertion:- If earth did not have atomos...

Assertion:- If earth did not have atomosphere, its average surface temperature would be lower than what it is now.
Reason:- Greenhouse effect of the atmosphre would be absent, if earth did not have atmosphere.

A

If both Assertion `&` Reason are True `&` the Reason is a correct explanation of the Assertion.

B

If both Assertion `&` Reason are True but Reason is not a correct explanation of the Assertion.

C

If Assertion is True but the Reason is False.

D

If both Assertion `&` Reason are False.

Text Solution

Verified by Experts

The correct Answer is:
A
Promotional Banner

Topper's Solved these Questions

  • TEST PAPERS

    ALLEN |Exercise Part-1 Physics|15 Videos

  • TEST PAPERS

    ALLEN |Exercise part-2 physics|73 Videos

  • TEST PAPERS

    ALLEN |Exercise PAPER 2|60 Videos

  • TEST PAPER 4

    ALLEN |Exercise PHYSICS|45 Videos

  • UNIT & DIMENSIONS, BASIC MATHS AND VECTOR

    ALLEN |Exercise Exercise (J-A)|7 Videos

Similar Questions

Explore conceptually related problems

If the earth did not have an atmosphere, would its average surface temperature be higher or lower than what it is now ?

If there were no atmosphere, the average temperature on the surface of earth would be :-

Assertion : If Earth doesn't have atmosphere, than there will be very much cold. Reason : In convection, heat transfers through air.

Explain why : (a) a body with large reflectivity is a poor emitter (b) a brass tumbler feels much colder than a wooden tray on a chilly day (c) an optical pyrometer (for measuring high temperatures calibrated for an ideal black body radiation gives too low a value for the temperature of a red hot Iron plece in the open, but gives a correct value for the temperature when the same plece is in the fumace (d) the earth without its atmosphere would be inhospitably cold (e) heating systems based on circulation of steam are more efficient in warming a building than those based on circulation of hot water

If a person goes to a height equal to radius of earth from its surface, what would be his weight relative to that on the earth ? And he goes to a same depth, what would be his weight? (i) For height h = Re

The earth's surface has a negative surface charge density of 10^(-9)C m ^(-2). The potential difference of 400 kV between the top of the atmosphere and the surface results (due to the low conductivity of the lower atmosphere) in a current of only 1800 A over the entire globe. If there were no mechanism of sustaining atmospheric electric field, how much time (roughly) would be required to neutralise the earth's surface? (This never happens in practice because there is a mechanism to replenish electric charges. namely tghe coontainual thunderstorms and lighting in different parts of the globe). (Radius of earth =6.37 xx 10 ^(6) m.)

ALLEN -TEST PAPERS-PAPER 3
  1. Assertion:- Any arbitrary displacement of charges inside a shell does ...

    Text Solution

    |

  2. Assertion:- Kirchhoff's voltage law indicates that field is conservati...

    Text Solution

    |

  3. Assertion:- Magnetism and superconductivity are natural enemies. Rea...

    Text Solution

    |

  4. Asseration: A metal piece and a non-metal (stone) piece are dropped fr...

    Text Solution

    |

  5. Assertion:- If earth did not have atomosphere, its average surface tem...

    Text Solution

    |

  6. Assertion:- Different colours of light have same velocity in vaccum, b...

    Text Solution

    |

  7. Assertion:- If an object placed on the optic axis of a lens is illumin...

    Text Solution

    |

  8. Assertion:- A simple microscope may have different magnification for d...

    Text Solution

    |

  9. Assertion : Newton's rings are formed in the reflected system. When th...

    Text Solution

    |

  10. Assertion:- A photocell is called an electric eye. Reason:- The elec...

    Text Solution

    |

  11. Assertion : Soft and hard X-rays differ in frequency as well as veloci...

    Text Solution

    |

  12. Assertion:In beta-decay, all the emitted electron do not have the same...

    Text Solution

    |

  13. Statement-I : To be used as amplifier, the transistor in the common em...

    Text Solution

    |

  14. Assertion:- Optical communication system is more economical than other...

    Text Solution

    |

  15. Assertion:- Two identical trains move in opposte sense in equatorial p...

    Text Solution

    |

  16. Statement-1: The size of a hydrogen increases as it rises in air. St...

    Text Solution

    |

  17. Assertion:- For Reynolds number R(e)gt2000m, the flow of fluid is turb...

    Text Solution

    |

  18. Assertion:- To drink chilled juicc, we use icc cubes of 0^(@)C. Reas...

    Text Solution

    |

  19. Assertion:- During adiabatic expansion of an ideal gas, temperature fa...

    Text Solution

    |

  20. Assertion:- Transvers waves are produced in a very long string fixed a...

    Text Solution

    |