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Assertion : When certain wavelength of l...

Assertion : When certain wavelength of light fall on metal surface it ejects electron.
Reason : Light was wave nature.

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are true but reason is not the correct explanation of assertion.

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given question, we need to analyze both the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states: "When certain wavelength of light falls on a metal surface, it ejects electrons." This statement refers to the photoelectric effect, which is a phenomenon where light (or electromagnetic radiation) incident on a metal surface can cause the emission of electrons from that surface. ### Step 2: Understand the Reason The reason states: "Light has wave nature." This statement refers to the wave-particle duality of light, where light exhibits properties of both waves and particles. However, the photoelectric effect specifically demonstrates the particle nature of light, as it involves photons (particles of light) striking the metal and transferring energy to electrons. ### Step 3: Analyze the Relationship While the reason states that light has wave nature, the assertion about the ejection of electrons is more accurately explained by the particle nature of light (photons). The photoelectric effect occurs when the energy of the incident photons exceeds the work function of the metal, leading to the ejection of electrons. ### Step 4: Conclusion - The assertion is true because the photoelectric effect does occur when light of certain wavelengths falls on a metal surface. - The reason is also true in a broader context, as light does exhibit wave properties; however, it does not correctly explain the assertion in the context of the photoelectric effect. Thus, the answer to the question is: **Both assertion and reason are true, but the reason is not the correct explanation for the assertion.** ### Final Answer The correct option is: **Both assertion and reason are true, but the reason is not the correct explanation for the assertion.** ---
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