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Assertion: Aeroplanes are made to run on...

Assertion: Aeroplanes are made to run on the runway before take off, so that they acquire the necessary lift.
Reason: This is as per Bernoulli's theorem.

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 and reason is false.

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the assertion and reason related to aeroplanes and Bernoulli's theorem, we can follow these steps: ### Step 1: Understand the Assertion The assertion states that aeroplanes run on the runway before take-off to acquire the necessary lift. This is true because, during take-off, the aircraft needs to reach a certain speed (take-off speed) to generate enough lift to become airborne. **Hint:** Consider why an aircraft needs speed to take off and how lift is generated. ### Step 2: Understand the Reason The reason provided states that this phenomenon is explained by Bernoulli's theorem. Bernoulli's theorem indicates that an increase in the speed of a fluid occurs simultaneously with a decrease in pressure. In the context of an airplane wing (airfoil), as the aircraft moves forward, the air moves faster over the top surface of the wing compared to the bottom surface. **Hint:** Recall the relationship between fluid speed and pressure as described by Bernoulli's theorem. ### Step 3: Connect Assertion and Reason To connect the assertion and reason, we can analyze how Bernoulli's theorem applies to the lift generated by an airplane wing. As the airplane accelerates down the runway, the air pressure above the wing decreases due to the increased velocity of air over the wing, while the pressure below the wing remains higher. This pressure difference creates lift, allowing the airplane to take off. **Hint:** Think about how the pressure difference is crucial for lift and how it relates to the speed of the airplane. ### Step 4: Conclusion Since the assertion is true (airplanes need to run to acquire lift) and the reason accurately explains the assertion using Bernoulli's theorem, we conclude that the reason is a correct explanation of the assertion. **Final Answer:** Both the assertion and reason are true, and the reason correctly explains the assertion.
To solve the question regarding the assertion and reason related to aeroplanes and Bernoulli's theorem, we can follow these steps: ### Step 1: Understand the Assertion The assertion states that aeroplanes run on the runway before take-off to acquire the necessary lift. This is true because, during take-off, the aircraft needs to reach a certain speed (take-off speed) to generate enough lift to become airborne. **Hint:** Consider why an aircraft needs speed to take off and how lift is generated. ### Step 2: Understand the Reason ...
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