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Assertion:We always see the same face of...

Assertion:We always see the same face of the moon
Reason : The period of rotation of the moon about its axis and its period of revolution about the earth are equal

A

Both Assertion and Reason are true and Reason is the correct explanation of Assertion

B

Both Assertion and Reason are true but Reason is not a correct explanation of Assertion

C

Assertion is true but Reason is false

D

Assertion is false but Reason is true

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason given. ### Step 1: Understand the Assertion The assertion states that "We always see the same face of the moon." This is a well-known phenomenon called "synchronous rotation" or "tidal locking," where the Moon rotates on its axis in the same amount of time it takes to orbit the Earth. **Hint:** Consider how the Moon's rotation relates to its orbit around the Earth. ### Step 2: Understand the Reason The reason states that "The period of rotation of the moon about its axis and its period of revolution about the earth are equal." The period of rotation (the time it takes for the Moon to complete one full rotation on its axis) is approximately 27.3 days, which is also the same time it takes for the Moon to orbit the Earth. **Hint:** Look into the definitions of period of rotation and period of revolution. ### Step 3: Compare the Periods Since both the period of rotation and the period of revolution are approximately 27.3 days, we can conclude that they are equal. This equality is what causes the same face of the Moon to always be visible from Earth. **Hint:** Think about what happens when two periods are equal in terms of visibility. ### Step 4: Conclusion Both the assertion and the reason are correct. Furthermore, the reason provides a correct explanation for the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion. **Final Answer:** Option A is the correct answer.
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