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Assertion :- A particle has positive acc...

Assertion `:-` A particle has positive acceleration it means that its speed always increases.
Reason `:-`Acceleration is the rate of change of speed with respect to time.

A

If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.

B

If both Assertion & Reason are True but Reason is not a correct explanation of the Assertiion.

C

If Assertion is True but the Reason is False.

D

If both Assertion & Reason are False

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Understand the Assertion The assertion states: "A particle has positive acceleration; it means that its speed always increases." - **Analysis**: Positive acceleration indicates that the velocity of the particle is increasing. However, speed is the magnitude of velocity. If a particle is moving in the negative direction (for example, -4 m/s) and then accelerates positively (to 2 m/s), its speed (which is a scalar quantity) does not always increase; it can decrease in this case. Therefore, the assertion is **false**. ### Step 2: Understand the Reason The reason states: "Acceleration is the rate of change of speed with respect to time." - **Analysis**: This statement is incorrect because acceleration is defined as the rate of change of **velocity** with respect to time, not speed. Speed is a scalar quantity, while velocity is a vector quantity that includes direction. Therefore, the reason is also **false**. ### Step 3: Conclusion Since both the assertion and the reason are false, we conclude that the correct answer is that both the assertion and reason are false. ### Final Answer Both assertion and reason are false. ---
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Knowledge Check

  • Assertion : For a particle, acceleration-time graph gives the velocity. Reason : Rate of change of velocity is acceleration.

    A
    If both assertion and reason are trure and reason is the correct explanation of assertion.
    B
    If both assertion and reason are true but reason is not the correct explanations of assertion.
    C
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    D
    If both assertion and reason is false

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