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A photoelectric cell is illuminated by a point source of light 1 m away. When the source is shifted to 2 m then:
Held on 30 Apr 2003 · Verified 9 Jul 2026.
each emitted electron carries one quarter of the initial energy
number of electrons emitted in half the initial number
each emitted electron carries half the initial energy
number of electrons emitted is a quarter of the initial number
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De-Broglie wavelength of an electron orbiting in the $n=2$ state of hydrogen atom is close to (Given Bohr radius $=0.052 \mathrm{~nm}$ )
Which of the following options represent the variation of photoelectric current with property of light shown on the x -axis? 
The maximum kinetic energy of photoelectrons from a surface with work function φ = 2 eV when light of λ = 4000 Å falls on it is (hc = 12400 eV·Å):
A full wave rectifier circuit with diodes $\left(D_1\right)$ and $\left(D_2\right)$ is shown in the figure. If input supply voltage $V_{\text {in }}=220 \sin (100 \pi t)$ volt, then at $t=15 \mathrm{msec}$ 
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