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The work function for the following meta...

The work function for the following metals is given: `Na: 2.75 eV, K: 2.30 eV, Mo: 4.17 eV, Ni: 5.15 ev`. Which of these metals will not give photoelectric emission for a radiation of wavelength `3300 Å` from a He-Cd laser placed 1 m away from the photocell? What happens if the laser is brought nearer and placed 50 cm away ?

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In Na and K photoelectric effect will take place.In Cd and Ni photoelectric effect will not take place
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