In a photoelectric experiment, the collector plate is at 2.0V with respect to the emitter plate made of copper `(phi)=4.5eV)`. The emitter is illuminated by a source of monochromatic light of wavelength 2000 `Å`nm.
In a photoelectric experiment, the collector plate is at 2.0V with respect to the emitter plate made of copper `(phi)=4.5eV)`. The emitter is illuminated by a source of monochromatic light of wavelength 2000 `Å`nm.
A
The maximum kinetic energy of the photoelctrons reaching the collector is `0`.
B
The maximum kinetic energy of the photoelctrons reaching the collector is `3.7` .eV.
C
If the polarity of the battery is reversed then answer to part A willl be 0
D
If the polarity of the battery is reversed then answer to part B will be `1.7 eV`
Text Solution
Verified by Experts
The correct Answer is:
B
`K_(max) = (1242)/(200) eV - 4.5 eV`
`K_(max) = 1.7 eV` at cathode
`K_(max) = (1.7 + 2) eV` at anode
If polarity is reversed, no `e^(-)` reach at collector.
`K_(max) = 1.7 eV` at cathode
`K_(max) = (1.7 + 2) eV` at anode
If polarity is reversed, no `e^(-)` reach at collector.
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