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प्रश्न
Can we find the mass of a photon by the definition p = mv?
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उत्तर
No, we cannot find the mass of a photon by the definition p = mv. The equation p = mv is valid only for objects that move with a velocity that is much slower than the speed of light. The momentum of a relativistic particle like photon is given by `pc = sqrt(E^2 - m^2c^4)`. A photon has zero rest mass. Therefore, on putting m = 0 in the equation, we get `p = E/c` , which is the valid equation for a photon.
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संबंधित प्रश्न
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The graph shows the variation of photocurrent for a photosensitive metal
- What does X and A on the horizontal axis represent?
- Draw this graph for three different values of frequencies of incident radiation ʋ1, ʋ2 and ʋ3 (ʋ3 > ʋ2 > ʋ1) for the same intensity.
- Draw this graph for three different values of intensities of incident radiation I1, I2 and I3 (I3 > I2 > I1) having the same frequency.
How would the stopping potential for a given photosensitive surface change if the intensity of incident radiation was decreased? Justify your answer.
