Question

in a photoelectric experiment, kinetic energy of photoelectron is 18.2 × 10^-19 J. the wavelength of incident light is X ×10^-8m , if work function of metal is 1eV, then value of X is ____.
(planks constant= 6.6×10^-34Js and 1eV =1.6×10^-19J)​

Answer 1

Answer:

Given, λ1 = 300n – m,

λ2 = 400n – m

Using Einstein equation for photoelectric effect,

E = hv = ϕ + eV0 ----(1)

Here, is work function of the metal and V0 is stopping potential

For λ1 wavelength's wave,

E1 = hv1 = ϕ + eV01

----(2)

Similarly, ----(3)

From Equations (2) and (3), we get

or

By using given values,

⇒ ΔV = 1.03V ≈ 1V