(A) The rotation of Saturn's rings and of double stars has been detected using the phenomenon of beats.
(B) Megaphone and ear trumpet work on the principle of interference of sound.

Options

A. Both A and B are true
B. Both A and B are false
C. A is true, B is false
D. A is false, B is true

Answer

**Step-by-step Solution:**

**Step 1: Analyze Statement A**
- The statement claims that the rotation of Saturn's rings and double stars has been detected using the phenomenon of beats.
- Beats are a phenomenon that occurs when two sound waves of slightly different frequencies interfere with each other, resulting in a fluctuation in sound intensity.

**Step 2: Consider the Medium for Sound**
- Sound requires a medium (like air, water, or solid materials) to travel. In space, including the regions around Saturn and between Earth and double stars, there is a vacuum.
- Since there is no medium in a vacuum, sound cannot travel through it.

**Step 3: Conclusion for Statement A**
- Since sound cannot travel in a vacuum, the detection of the rotation of Saturn's rings and double stars using beats is not possible.
- Therefore, Statement A is incorrect.

**Step 4: Analyze Statement B**
- The statement claims that megaphones and ear trumpets work on the principle of interference of sound.
- Interference of sound occurs when two or more sound waves overlap and combine, which can create constructive or destructive interference.

**Step 5: Understand the Function of Megaphones and Ear Trumpets**
- Megaphones and ear trumpets are designed to direct sound waves and amplify sound.
- They primarily work on the principle of reflection and focusing of sound waves, rather than interference.

**Step 6: Conclusion for Statement B**
- Since megaphones and ear trumpets utilize reflection to amplify sound rather than interference, Statement B is also incorrect.

**Final Conclusion:**
- Both statements A and B are false.

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