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 Interger).[Use : √3=1.73,h=6.63×10−34Jsme=9.1×10−31kg;c=3.0×108ms−1;1eV=1.6×10−19J]

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

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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 Interger).[Use : √3=1.73,h=6.63×10−34Jsme=9.1×10−31kg;c=3.0×108ms−1;1eV=1.6×10−19J]

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