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Assertion: In general |Displacement| le ...

Assertion: In general |Displacement| `le` distance.
Reason: The instantaneous speed is equal to the magnitude of the instantaneous velocity,

A

a.If both assertion `&` Reason are True `&` the Reason is a corrrect explanation of the Asserion.

B

b.If both Assertion `&` Reason are True but Reason is not correct explanation of the Assertion.

C

c.If Assertion is Trie but the Reason is False.

D

d.If both Assertion `&` Reason are false

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given problem, we need to analyze the assertion and reason provided in the question. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that in general, the magnitude of displacement is less than or equal to the distance traveled. - Displacement is defined as the shortest straight-line distance from the initial position to the final position of an object, while distance is the total length of the path traveled by the object. 2. **Analyzing the Assertion**: - Consider a particle moving along a path. If the particle moves from point A to point B, the distance traveled could be longer if the path is not straight (e.g., if it takes a detour). - For example, if a particle moves 4 meters north and then 3 meters east, the total distance traveled is \(4 + 3 = 7\) meters, while the displacement (the straight line from the starting point to the endpoint) can be calculated using the Pythagorean theorem: \[ \text{Displacement} = \sqrt{(4^2 + 3^2)} = \sqrt{16 + 9} = \sqrt{25} = 5 \text{ meters}. \] - Hence, in this case, \( \text{Distance} (7 \text{ m}) > \text{Displacement} (5 \text{ m}) \). 3. **Conclusion on Assertion**: - From the above example, we can conclude that the assertion is true: \( |\text{Displacement}| \leq \text{Distance} \). 4. **Understanding the Reason**: - The reason states that the instantaneous speed is equal to the magnitude of the instantaneous velocity. - Instantaneous speed is defined as the limit of the average speed as the time interval approaches zero, which mathematically can be expressed as: \[ v_{\text{instantaneous}} = \frac{dx}{dt}. \] - Instantaneous velocity, on the other hand, is defined as the rate of change of displacement with respect to time, which is also given by: \[ v_{\text{velocity}} = \frac{d(\text{Displacement})}{dt}. \] 5. **Conclusion on Reason**: - Since instantaneous speed is always a non-negative quantity and instantaneous velocity can be negative (depending on the direction), the magnitude of instantaneous velocity is indeed equal to instantaneous speed: \[ v_{\text{instantaneous}} = |v_{\text{velocity}}|. \] - Therefore, the reason is also true. 6. **Final Conclusion**: - Both the assertion and reason are true. However, the reason does not provide a correct explanation for the assertion. Thus, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.
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  15. Assertion: In projectile motion, when horizontal range is n times the ...

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