Assertion (A): A boat cannot move upstream if the stream flows faster than the boat moves in still water.
Reason (R): The upstream speed is $b - s$ .

Both A and R are true, and R is the correct explanation of A.Correct answerYour answerBoth A and R are true, but R is not the correct explanation of A.Correct answerYour answerA is true, but R is false.Correct answerYour answerA is false, but R is true.Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

R is the rule for upstream speed. True.
If $s > b$ , then $b - s < 0$ : the boat is carried back, so A is true because of R.

Concept: Facts about boats and streams
Typical timeTypical: 60 s
Your timeYours: —

The rule this testsJourneys on a river

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Assertion (A): A boat cannot move upstream if the stream flows faster than the boat moves in still water.Reason (R): The upstream speed is b−sb - sb−s.

Explanation

Assertion (A): A boat cannot move upstream if the stream flows faster than the boat moves in still water.
Reason (R): The upstream speed is $b - s$ .