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STATEMENT-1: A man can cross river of wi...

STATEMENT-1: A man can cross river of width `d` in minimum time `t`. On increasing river velocity, minimum time to cross the river by man will remain uncharged.
STATEMENT-2: Velocity of river is perpendicular to width of river. So time to cross the river is independent of velcoity of river.

A

Statement -1 is True, Statement-2 is Ture, Statement-2 is a correct explanantion for Statement-1.

B

Statement-1 is Ture, Statement-2 is Ture, Statement-2 is Not a correct explanantion for Statement-1.

C

Statement-1 is True, Statement-2 is False.

D

Statement-1 is False, Statement-2 is True.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the two statements provided and determine their validity based on the principles of kinematics. ### Step-by-Step Solution: 1. **Understanding the Problem**: - We have a river of width \( d \). - A man can cross this river in a minimum time \( t \). - We need to evaluate the effect of increasing the river's velocity on the time taken to cross. 2. **Analyzing Statement 1**: - The statement claims that if the river's velocity increases, the minimum time \( t \) to cross the river will remain unchanged. - To analyze this, we need to consider the direction of the river's flow and the man's crossing. 3. **Analyzing Statement 2**: - This statement asserts that the velocity of the river is perpendicular to the width of the river. - Since the river's velocity is perpendicular, it does not affect the time taken to cross the river. 4. **Determining the Time to Cross the River**: - The time \( t \) to cross the river can be calculated using the formula: \[ t = \frac{d}{v_m} \] where \( v_m \) is the velocity of the man crossing the river. - The river's velocity \( v_r \) does not enter this equation because it is perpendicular to the direction of crossing. 5. **Conclusion on Statement 1**: - Since the time to cross the river depends only on the width \( d \) and the man's velocity \( v_m \), increasing the river's velocity \( v_r \) does not change the minimum time \( t \). - Therefore, Statement 1 is **true**. 6. **Conclusion on Statement 2**: - Since the river's velocity is indeed perpendicular to the width of the river, it confirms that the time to cross is independent of the river's velocity. - Therefore, Statement 2 is also **true**. 7. **Final Evaluation**: - Both statements are true, and Statement 2 correctly explains Statement 1. - Thus, the answer is **A**: Both statements are true, and Statement 2 is the correct explanation for Statement 1.
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