# physics

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A boat is ravelling in a river with a current of 3 km/hr. The boat is capable of travelling at 10 km/hr in still water. How long will it take the boat to travel 7km upstream

• physics -

The boat velocity relative to land, going upstream, is 10 - 3 = 7 km/h

Time to travel 7 km
= 7 km/(7 km/h)
= 1 hour

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