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Assertion A pulsar is a source of radio ...

Assertion A pulsar is a source of radio waves that varies in intensity at regular intervals
Reason A pulsar is a rotating neutron star

A

Both 'A' and 'R' are true and 'R' is the correct explanation of 'A'.

B

Both 'A' and ’R' are true and 'R' is not the correct explanation of 'A

C

A' is true and 'R' is false

D

'A' is false and R' is true

Text Solution

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The correct Answer is:
A
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AAKASH SERIES-ELECTROMAGNETIC WAVES-EXERCISE -IB
  1. (A ): E.M. waves can show diffraction effect (R) : E.M waves are trans...

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  2. (A ): In electromagnetic wave, electric and magnetic fields oscillate ...

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  3. (A ): The light can travel in vacuum but sound cannot do so (R) : Ligh...

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  4. (A): Gamma rays are more energetic than X-rays (R) : Gamma rays are of...

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  5. Assertion : The earth without its atmosphere would be inhospitably col...

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  6. A : Environmental damage has depleted the ozone layer in the atmosphe...

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  7. (A) : The microwaves are better carriers of signals than radio waves. ...

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  8. Assertion (A) : The presence of CO(2) in the air accelerates corrosio...

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  9. A satellite orbiting close to the surface of earth does not fall down ...

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  10. (A) : The average magnitude of poynting vector vecS is the intensity o...

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  11. A : Long distance radio broadcasts use short-wave bands. R : Ionosp...

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  12. A : It is necessary to use satellites for long distance TV transmissi...

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  13. A : Optical and radio telescopes are built on the ground but X-ray ...

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  14. The ozone layer on the top of the stratosphere is crucial for human su...

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  15. Assertion A pulsar is a source of radio waves that varies in intensity...

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  16. (A) : Quasar emits radiowaves more than radio galaxy. (R) : Quasar has...

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  17. (A) : Dipole oscillations produce electro­magnetic waves. (R) : Accel...

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  18. Assertion (A): wedge(m(H^(o+))) and wedge(m(overset(c)(O)H)) ions are ...

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  19. (A) : In electromagnetic waves electric field and magnetic field lines...

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  20. The transverse nature of electromagnetic waves is proved by which of t...

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