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प्रश्न
The following graph shows the variation of photocurrent for a photosensitive metal :
(a) Identify the variable X on the horizontal axis.
(b) What does the point A on the horizontal axis represent?
(c) Draw this graph for three different values of frequencies of incident radiation v1, v2 and v3 (v1 > v2 > v3) for same intensity.
(d) Draw this graph for three different values of intensities of incident radiation I1, I2 and I3 (I1 > I2 > I3) having same frequency.
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उत्तर
(a) Variable X is the accelerating potential applied across the photosensitive material.
(b) A represents the stopping potential for the given photosensitive metal. Stopping potential is the minimum negative potential V0 applied across the photosensitive material at which the photoelectric current becomes zero.
(c) Graph for three different values of frequencies of incident radiation v1, v2 and v3 (v1 > v2 > v3) for same intensity
(d) Graph for three different values of intensities of incident radiation I1, I2 and I3 (I1 > I2 > I3) having same frequency
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- Can you explain how photoelectric effect was observed instantaneously?
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| The figure shows the variation of photoelectric current measured in a photocell circuit as a function of the potential difference between the plates of the photocell when light beams A, B, C and D of different wavelengths are incident on the photocell. Examine the given figure and answer the following questions: |
- Which light beam has the highest frequency and why?
- Which light beam has the longest wavelength and why?
- Which light beam ejects photoelectrons with maximum momentum and why?
- Assertion (A): For the radiation of a frequency greater than the threshold frequency, the photoelectric current is proportional to the intensity of the radiation.
- Reason (R): Greater the number of energy quanta available, the greater the number of electrons absorbing the energy quanta and the greater the number of electrons coming out of the metal.
