Physics · 2021
JEE Main · 26 August 2021, Shift 1 · Q7
In a photoelectric experiment ultraviolet light of wavelength 280 nm is used with lithium cathode having work function φ=2.5 eV. If the wavelength of…
In a photoelectric experiment ultraviolet light of wavelength $\displaystyle 280$ nm is used with lithium cathode having work function $\displaystyle \phi=2.5 \mathrm{eV}$. If the wavelength of incident light is switched to $\displaystyle 400$ nm , find out the change in the stopping potential. $\displaystyle \left(\mathrm{h}=6.63 \times 10^{-34} \mathrm{Js}, \mathrm{c}=3 \times 10^8 \mathrm{~ms}^{-1}\right)$
Official answer
(1)
1.$\displaystyle 3$ V
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