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When a ship goes back and forth between a and B, assuming that the speed of the ship in still water does not change, the time it takes for the ship to go back and forth once when the water velocity increases______ (a) no change (b) increase (c) decrease (d) increase or decrease is possible
Let the distance between a and B be s, and the velocity in still water be V, then the time of one round trip in still water is T1 = 2sv. Let the water velocity be x, then the velocity along water is V + X, and the velocity against water is v-x. at this time, the time of one round trip is T2 = SV + X + SV − x = 2svv2 − x2 > 2svv2 = 2sv = T1
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