Representing the stopping potential V along y-axis and `((1)/(lamda))` along x-axis for a given photocathode, the curve is a straight line, the slope of which is equal toA. `(e)/(hc)`B. `(hc)/(e)`C. `(ec)/(h)`D. `(e)/(W)`

Representing the stopping potential V along y-axis and `((1)/(lamda))`

1.	Representing the stopping potential V along y-axis and `((1)/(lamda))` along x-axis for a given photocathode, the curve is a straight line, the slope of which is equal toA. `(e)/(hc)`B. `(hc)/(e)`C. `(ec)/(h)`D. `(e)/(W)`
Answer» Correct Answer - B The maximum KE of the photoelectron is given by `((1)/(2)mv^2)_(max)=hv-W` Now, `v=(c)/(lamda)` and `((1)/(2)mv^2)=eV` `eV=(hc)/(lamda)-W` or `V=((hc)/(e))(1)/(lamda)-(W)/(e)` Slope of straight line `=(hc)/(e)` Intercept of straight line `=-((W)/(e))`

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Representing the stopping potential V along y-axis and `((1)/(lamda))` along x-axis for a given photocathode, the curve is a straight line, the slope of which is equal toA. `(e)/(hc)`B. `(hc)/(e)`C. `(ec)/(h)`D. `(e)/(W)`

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