When light of wavelength 248 nm falls on a metal of threshold energy 3.0 eV, the de-Broglie wavelength of emitted electrons is ∘A. (Round off to the nearest Integer).[Use:√3=1.73; h=6.63×10−34 J s;me=9.1×10−31 kg; c=3.0×108 m s−1; 1 eV=1.6×10−19 J]

When light of wavelength 248 nm falls on a metal of threshold energy 3

1.	When light of wavelength 248 nm falls on a metal of threshold energy 3.0 eV, the de-Broglie wavelength of emitted electrons is ∘A. (Round off to the nearest Integer).[Use:√3=1.73; h=6.63×10−34 J s;me=9.1×10−31 kg; c=3.0×108 m s−1; 1 eV=1.6×10−19 J]
Answer» When light of wavelength $248 nm$ falls on a metal of threshold energy $3.0 eV$ , the de-Broglie wavelength of emitted electrons is $\circ A$ . (Round off to the nearest Integer). $[Use : \sqrt{3} = 1.73; h = 6.63 \times 10^{- 34} J s; m_{e} = 9.1 \times 10^{- 31} kg; c = 3.0 \times 10^{8} {m s}^{- 1}; 1 eV = 1.6 \times 10^{- 19} J]$

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When light of wavelength 248 nm falls on a metal of threshold energy 3.0 eV, the de-Broglie wavelength of emitted electrons is ∘A. (Round off to the nearest Integer).[Use:√3=1.73; h=6.63×10−34 J s;me=9.1×10−31 kg; c=3.0×108 m s−1; 1 eV=1.6×10−19 J]

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