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The magnetic field associated with a light wave is given, at the origin, by B = B 0 [sin(3.14 × 10 7 )ct + sin(6.28 × 10 7 )ct]. If this light falls on a silver plate having a work function of 4.7 eV, what will be the maximum kinetic energy of the photo electrons? (c = 3 × 10 8 ms –1 , h = 6.6 × 10 –34 J-s)

1. 6.82 eV
2. 8.52 eV
3. 12.5 eV
4. 7.72 eV

Correct answer: 7.72 eV

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