The work function of a certain metal is 3.31 × 10-19 J. Then, the maximum kinetic energy of photoelectrons emitted by incident radiation of wavelength 5000 mathringA is (Given, h=6.62 × 10-34 J - s , c =3 × 108 ms -1, .e=1.6 × 10-19 C )

Question

The work function of a certain metal is 3.31 × 10-19 J. Then, the maximum kinetic energy of photoelectrons emitted by incident radiation of wavelength 5000 mathringA is (Given, h=6.62 × 10-34 J - s , c =3 × 108 ms -1, .e=1.6 × 10-19 C ) (A) 2.48 eV (B) 0.41 eV (C) 2.07 eV (D) 0.82 eV

Tardigrade Admin · Accepted Answer

Work function W0=3.31×10-19 J Wavelength of incident radiation λ=5000×10-10 m E=W0+KE According to Einstein's equation ⇒ (hc/λ)=3.31×10-19+KE KE=-3.31×10-19+(6.62×10-34×3×108/5000×10-10) =-3.31×10-19+(6.62×3/5)×10-19 =(-3.31×1.324×3)×10-19 =(3.972-3.31)×10-19 =0.662×10-19 J or E=(0.662×10-19/1.6×10-19) =0.41 eV

Q. The work function of a certain metal is 3.31×10−19J. Then, the maximum kinetic energy of photoelectrons emitted by incident radiation of wavelength 5000A˚ is (Given, h=6.62×10−34J−s,c=3×108ms−1,e=1.6×10−19C)

2.48 eV

0.41 eV

2.07 eV

0.82 eV

Q. The work function of a certain metal is $3.31 \times 1 0^{- 19} J$ . Then, the maximum kinetic energy of photoelectrons emitted by incident radiation of wavelength $5000 \overset{˚}{A}$ is
(Given, $h = 6.62 \times 1 0^{- 34} J - s, c = 3 \times 1 0^{8} m s^{- 1}, e = 1.6 \times 1 0^{- 19} C)$