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A : The centre of sensitivity of our eye...

A : The centre of sensitivity of our eyes coincides with the centre of the wavelength distribution of the sun.
R : Humans have evolved with visions most sensitive to the strongest wavelength from the sun.

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)

C

If assertion is true statement but Reason is false, then mark (3)

D

If both Assertion and Reason are false statements, then mark (4)

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the assertion (A) and the reason (R) given in the statement. ### Step-by-Step Solution: 1. **Understanding the Assertion (A)**: - The assertion states that "The centre of sensitivity of our eyes coincides with the centre of the wavelength distribution of the sun." - The human eye has photoreceptors known as cones, which are sensitive to different wavelengths of light. The cones are divided into three types based on their sensitivity: short (S), medium (M), and long (L) wavelengths. - The sensitivity ranges for these cones are approximately: - Short (S): 420 to 440 nm - Medium (M): 530 to 540 nm - Long (L): 560 to 580 nm - The sun emits light across a spectrum, with a peak sensitivity in the visible range. The assertion is correct because the peak sensitivity of our eyes aligns with the wavelengths emitted by the sun. 2. **Understanding the Reason (R)**: - The reason states that "Humans have evolved with visions most sensitive to the strongest wavelength from the sun." - While it is true that human vision is adapted to detect visible light, the statement implies that humans can see all electromagnetic waves, which is incorrect. Humans can only see a small portion of the electromagnetic spectrum (visible light), while other wavelengths like radio waves and infrared are not visible to the human eye. - Therefore, while the reason has some truth to it regarding evolution and sensitivity to sunlight, it is misleading as it suggests that humans can see all wavelengths. 3. **Conclusion**: - The assertion (A) is true, while the reason (R) is false. - Thus, the correct answer is that the assertion is true and the reason is false. ### Final Answer: - **Assertion (A)**: True - **Reason (R)**: False - **Correct Option**: 3
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