Light of wavelength `5,500 overset @A` falls on a sensitive plate with work function 1.7 eV .Find stopping potential.

Explanation

`lambda = 5000 Å = 5000 xx 10^(-10) m`
`lambda= 5 xx 10^(-7) m`
Work function `= phi_0 = 1.68 eV `
Stopping Potential = `V_s = ?`
Energy of incident radiation= `E = (hc)/(lambda)`
`E = (6.62 xx 10^(-34) xx 3 xx 10^8)/(5 xx 10^(-7))`
`E = (19.86)/5 xx 10^(-34 + 8 + 7)`
`E = 3.972 xx 10^(-19)J`
`E = (3.972 xx 10^(-19))/(1.6 xx 10^(-19)) eV`
`E = 2.48 eV`
Now `eV_s = E - phi_0 = 2.48 - 1.68`
`eV_s = 0.8 eV`
`V_s = 0.8` volt.