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Assertion: Photons can exist at rest. ...

Assertion: Photons can exist at rest.
Reason: Rest mass `m_0=msqrt(((1-v^2)/(c^2)))`
`because` v = c (speed of light) `therefore` `m_0=0`

A

Assertion is True, Reason is True,
Reason is a correct explanation for Assertion.

B

Assertion is True, Reason is True,
Reason is not a correct explanation for Assertion.

C

Assertion is True, Reason is False.

D

Assertion is False, Reason is True.

Text Solution

Verified by Experts

The correct Answer is:
D
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TARGET PUBLICATION-ELECTRONS AND PHOTONS-Evaluation Test
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  5. When a monochromatic point source of light is at a distance of 0.2 m f...

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  6. Assertion: Work function of a metal is 4 eV. The maximum wavelength of...

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  7. Eye of an experimenter detects the green light (lambda =5000 Å) at 5xx...

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  8. Photon having wavelength lambda = 3.5xx10^(-7)m and lambda = 5.4xx10^(...

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  9. Illuminating a metal surface alternately with wavelengths lambda1 and ...

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  10. In a photoelectric effect, the anode potential is plotted against the ...

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  11. A proton when accelerated through a potential difference of V volt has...

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  12. The work function for the following metals is given Na: 2.75 eV, K:2.3...

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  13. Assertion: Work function of a metal is proportional to maximum wavelen...

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  14. The retarding potential for having zero photoelectron current

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  15. A proton and an alpha-particle are accelerated through same potential ...

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  16. Light of wavelength 3000 Å falls on a sensitive surface. If the surfac...

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  17. The work function for aluminium is 4.125 eV. The cut-off wavelength fo...

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  18. Lights of two different frequencies whose photons have energies 1 eV a...

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  19. When a metal surface is illuminated by a monochromatic light of wave-l...

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