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Electrons are emitted with zero velocity from a metal surface when it ...

Electrons are emitted with zero velocity | Class 11 Chemistry Chapter Structure of Atom, Structure of Atom NCERT Solutions

Question:

Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wavelength 6800 Å. Calculate threshold frequency (v₀) and work function (W₀) of the metal.

Answer:

Given λ = 6800 amgstrom or 6800x 10^-10 m = 6.8 x 10^-7m

C = 3 x 10⁸ m/s

Also λ = c/v or v = c/ λ Therefore putting the values in the equation, we get

=3 x 10⁸ / 6.8 x 10^-7m = 4.41 x 1014 s^-1

Hence, work function (W₀) of the metal = hν₀

= (6.626 × 10^–34 Js) (4.41 × 10¹⁴ s^–1)

= 2.922 × 10^–19 J

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Comments

Katha Ghosh
2019-12-09 17:47:31

Thanks

Arpita Mohanty
2019-08-06 10:48:49

Work function=h*threshold frequency Not h*frequency

Bandit singh
2019-06-01 12:13:12

Thanx

Zawed Alam
2019-05-05 22:49:21

Thanks

Zawed Al
2019-05-05 22:48:27

Thaks

Susmita paul
2019-01-16 17:21:39

Thank you so much

Bill Gates
2018-09-17 15:49:58

Thank you very much

Anupam sharma
2018-07-15 16:10:46

Tq very much

priya
2018-07-08 19:45:41

velocity of light

ath
2016-06-29 08:38:10

c is what and how 3*10*8

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Welcome to the NCERT Solutions for Class 11 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 12: Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wav....

Electrons are emitted with zero velocity | Class 11 Chemistry Chapter Structure of Atom, Structure of Atom NCERT Solutions

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