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Question
The figure shows a plot of stopping potential (V0) versus `1/lambda`, where λ is the wavelength of the radiation causing photoelectric emission from a surface. The slope of the line is equal to ______.
Options
Φ0
`h/e`
`(hc)/e`
`(h^2c)/e^2`
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Solution
The figure shows a plot of stopping potential (V0) versus `1/lambda`, where λ is the wavelength of the radiation causing photoelectric emission from a surface. The slope of the line is equal to `underlinebb(h/e)`.
Explanation:
`1/lambda = ν` (frequency)
The photoelectric effect in terms of stopping potential is as follows:
hν = hν0 + eV
Writing this equation in terms of y = mx + c, we get
V = `((hν - hν_0))/e`
On comparing this equation with y = mx + c, we get
`m = h/e`
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