Question

Find the kinetic energy of an electron (in eV) emitted by a metal when light of wavelength 3105 angstrom falls on it
threshold wavelength is 6210 angstrom)​

Answer 1

Question

Find the kinetic energy of an electron (in eV) emitted by a metal when light of wavelength 3105 angstrom falls on it

threshold wavelength is 6210 angstrom)

Answer

E = 0.1eV

Answer 2

Explanation:

Energy of photon=

λ/hc joules

λ=2200A⁰

Work function ϕ=4.1eV

1eV=1.6×10

−19 joules

(a) E=λ(A⁰ )/12375 eVE=5.6eV

(b)maximum Kinetic energy KEmax=E−ϕ

KEmax=5.6−4.1=1.5eV

(c)stopping potential= KEmax/e

stopping potential=1.5V