Monochromatic light with a frequency well above the cutoff frequency i...
Introduction:
The photoelectric effect refers to the emission of electrons from a material when it is illuminated with light of sufficient energy. The intensity and frequency of the incident light play a crucial role in determining the photoelectric current.
Effect of Frequency on Photoelectric Current:
The photoelectric current is directly proportional to the intensity of the incident light but is dependent on the frequency of the light as well. When monochromatic light with a frequency above the cutoff frequency is incident on the emitter, electrons are emitted due to the absorption of photons. The cutoff frequency is the minimum frequency required to remove electrons from the material.
Increasing Frequency while Keeping Intensity Constant:
Now, let's consider the scenario where the frequency of the incident light is doubled while keeping the intensity constant. This means that the photons have twice the energy compared to the initial frequency.
Effect on Photoelectric Current:
The photoelectric current is determined by the number of electrons emitted per unit time. Here's how the change in frequency affects the photoelectric current:
1. Increased Energy: Doubling the frequency of the light results in photons with twice the energy. Therefore, each photon carries more energy to dislodge electrons from the material.
2. Increased Kinetic Energy of Electrons: The increased energy of the photons leads to electrons being emitted with higher kinetic energy. Higher kinetic energy results in faster-moving electrons.
3. Unchanged Photoelectrons: The number of photoelectrons emitted per unit time remains the same as long as the intensity of the light is constant. Each incident photon can still only remove one electron.
4. Unchanged Photoelectric Current: Since the number of emitted photoelectrons per unit time remains constant, the photoelectric current also remains the same. The photoelectric current depends on the rate at which electrons are emitted, which is independent of the energy of individual photons.
Conclusion:
In conclusion, doubling the frequency of monochromatic light while keeping the intensity constant does not affect the photoelectric current. The number of emitted photoelectrons per unit time remains the same, leading to an unchanged photoelectric current.
Monochromatic light with a frequency well above the cutoff frequency i...
Same because if we draw graph between current &frequency it will be parallel to the frequency means no change in current & on doubling frequency photoelectric current not changed
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