MCQ
$UV$ light of $4.13 \ eV$ is incident on a photosensitive metal surface having work function $3.13 \ eV .$ The maximum kinetic energy of ejected photoelectrons will be $:$
- A4.13 Ev
- B1 eV
- C3.13 eV
- D7.26 eV
✓
Answer
$ E _{\text {photon }}=\text { (work function) }+ K \cdot E _{\max }$
$\therefore 4 \cdot 13=3 \cdot 13+ K \cdot E _{\max }$
$\therefore K \cdot E _{\max }=1 eV $
$\therefore 4 \cdot 13=3 \cdot 13+ K \cdot E _{\max }$
$\therefore K \cdot E _{\max }=1 eV $
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