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Assertion : Thrust on a rocket depends o...

Assertion : Thrust on a rocket depends only on velocity of exhaust gases Rate of decrease of mass is irrelevant
Reason : Larger the velocity greater is the thrust .

A

If both assertion and Reason are true and the Reason is the correct explanation of the assertion.

B

If both assertion and Reason are true but the reason is not the correct explanation of the assertion

C

If assertion is true but reason is false

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states that "Thrust on a rocket depends only on the velocity of exhaust gases; the rate of decrease of mass is irrelevant." **Analysis**: This statement is incorrect. The thrust of a rocket is not solely dependent on the velocity of the exhaust gases. It also depends on the rate at which the mass of the rocket is decreasing (i.e., the mass flow rate of the exhaust gases). ### Step 2: Understand the Reason The reason states that "Larger the velocity, greater is the thrust." **Analysis**: This statement is correct. According to the rocket thrust equation (T = ṁ * v_e), where T is thrust, ṁ is the mass flow rate, and v_e is the velocity of the exhaust gases, an increase in the velocity of the exhaust gases does indeed lead to an increase in thrust, assuming the mass flow rate remains constant. ### Step 3: Conclusion Since the assertion is false (it overlooks the importance of the mass flow rate), while the reason is true (it correctly states that greater velocity leads to greater thrust), we conclude that the assertion and reason are not in agreement. **Final Answer**: The assertion is false, and the reason is true.
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