The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are <math> <mn>2.14</mn> <mi mathvariant="normal">e</mi> <mi mathvariant="normal">V</mi> <mo>,</mo> <mn>2.30</mn> <mi mathvariant="normal">e</mi> <mi mathvariant="normal">V</mi> </math> and <math> <mn>2.75</mn> <mi mathvariant="normal">e</mi> <mi mathvariant="normal">V</mi> </math> respectively. If incident electromagnetic radiation has an incident energy of <math> <mn>2.20</mn> <mi mathvariant="normal">e</mi> <mi mathvariant="normal">V</mi> </math> , which of these photosensitive surfaces may emit photoelectrons? &lt;!-- [if !supportLineBreakNewLine]--&gt; &lt;!--[endif]--&gt;

Cs only

Na only

Both Na and k

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Photoelectric Emission Dual Nature of Radiation and Matter Physics Class 12th

The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are $2.14 e V, 2.30 e V$ and $2.75 e V$ respectively. If incident electromagnetic radiation has an incident energy of $2.20 e V$ , which of these photosensitive surfaces may emit photoelectrons?

Option 1 -

Na only

Option 2 -

Cs only

Option 3 -

Both Na and k

Option 4 -

K only

2 Views | Posted 3 weeks ago

Asked by Shiksha User

1 Answer

Answered by

Raj Pandey | Contributor-Level 9

3 weeks ago

Correct Option - 2

Detailed Solution:

Incident energy $= 2.20 e V$

If $? < 2.20 e V$ electron will emit.

$? > 2.20 e V$ No electron emission

Only caesium will emit electron

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The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are $2.14 e V, 2.30 e V$ and $2.75 e V$ respectively. If incident electromagnetic radiation has an incident energy of $2.20 e V$ , which of these photosensitive surfaces may emit photoelectrons?

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The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are 2.14 e V , 2.30 e V and 2.75 e V respectively. If incident electromagnetic radiation has an incident energy of 2.20 e V , which of these photosensitive surfaces may emit photoelectrons?

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The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are $2.14 e V, 2.30 e V$ and $2.75 e V$ respectively. If incident electromagnetic radiation has an incident energy of $2.20 e V$ , which of these photosensitive surfaces may emit photoelectrons?