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Given below are two statements : one is labelled Assertion A and the other is labelled Reason R. Assertion A : An electron microscope can achieve better resolving power than an optical microscope. Reason R : The de Broglie's wavelength of the electrons emitted from an electron gun is much less than wavelength of visible light. In the light of the above statements, choose the correct answer from the options given below: (1) A is true but R is false. (2) Both A and R are true and R is the correct explanation of A. (3) Both A and R are true but R is NOT the correct explanation of A. (4) A is false but R is true.

1. (1) A is true but R is false.
2. (2) Both A and R are true and R is the correct explanation of A.
3. (3) Both A and R are true but R is NOT the correct explanation of A.
4. (4) A is false but R is true.

Correct answer: (2) Both A and R are true and R is the correct explanation of A.

Solution

The assertion is correct because electron microscopes utilize electrons, which have much shorter wavelengths than visible light, allowing them to resolve finer details. The reason accurately explains this phenomenon, as the shorter de Broglie wavelength of electrons directly contributes to the improved resolving power of electron microscopes compared to optical microscopes.

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