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Readme [11.4K]
3 years ago
15

A man can swim with a speed of 5m/s in calm water. if this man swims crosses a specific river his speed is 3m/s. if he takes the

minimum time to cross the river find the speed of the flow of water in the river...
plz answer me with all the steps!
I'll give u points ..mark brainliest and follow u ​
Physics
1 answer:
Alex787 [66]3 years ago
4 0

Answer:

The speed of the flow of water in the river is 4 m/s.

Explanation:

Given that,

Speed of man = 5 m/s

If this man swims crosses a specific river his speed is 3 m/s.

If he takes the minimum time to cross the river

Let the speed of flow of water be v_{r}

We need to calculate the speed of the flow of water in the river

Using formula for velocity

v_{rs}^2=v_{r}^2+v_{s}^2

v_{r}^2=v_{rs}^2-v_{s}^2

Where, v_{s} = velocity of swimmer

v_{sr} = relative velocity

v_{r} = velocity of river

Put the value into the formula

v_{r}^2=5^2-3^2}

v_{r}=\sqrt{5^2-3^2}

v_{r}=4\ m/s

Hence, The speed of the flow of water in the river is 4 m/s.

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