The stopping potential in a photoelectric experiment is linearly related to the inverse of the wavelength `(1/lambda)` of the light falling on the cathode. The potential difference applied across an X-ray tube is linearly related to the inverse of the cutoff wavelength `(1/lambda)` of the X-ray emitted. Show that the slopes of the lines in the two cases are equal and find its value.

Explanation

` V_0-Stoping Potential `
` K=Potential difference across X-ray tube `
` lambda-Wavelength `
` lambda- Cut difference Wavelength `
` eV_0=hf-hf_0 `
` lambda=(hc)/(eV) `
` eV_0=(hc)/lambda `
` or, Vlambda=(hc)/e `
` or, V_0lambda=(hc)/e `
` Here Slopes are same `
` i.e. V_0lambda=Vlambda `
` (hc)/e=(6.63xx10^-34xx3xx10^8)/(1.6xx10^-19) `
` =1.242xx10^-6Vm`