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The kinetic energy of electron emitted bya metal sheet of work function 5eV whenphotons from EMR of wavelength 62nmstrike the metal plate is:(with proper steps) |
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Answer» Answer: Explanation: The wavelength of the electron EMITTED by a metal sheet of work function 5 eV when photons from EMR of wavelength 62 nm strike the metal plate . For metal A, de-broglie wavelength (λ A )= mv A
−−−−−−1 ⇒V A = mλ A
h
4.25−W A = 2 1 ×m× m 2 ×A 2
h 2
⇒4.25−W A = 2mλA 2
h 2
−−−−−−2 For metal B, 4.7−W B = 2mλ A
2
h 2
−15−−−−−3 and λ B= mv B
h ⇒2λ A = mv Bh ⇒V B= 2mλ -A h −−−−−4 So, from difference in kinetic energy, ⇒−T B+T A =1.5−−−−x and solving (i),(ii),(iii),(iv) and (v) simultaneously we find, W A =2.25eV |
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