Grade 11Mechanics

A swimmer can swim in still water with a speed of 5m/s.While crossing a river his average speed is 3m/s.If he crosses the river in shortest possible time,what is speed of flow of water?

Savitri Yadav

9 Years agoGrade 11

3 Answers

sumanth

9 Years ago

if swimmer can swim in still water with a speed of 5m/s while crossing a river his average speed is 3m/s

so then the speed of the water flow is 2m/s

Vedant

7 Years ago

Here v_s_r=5m/s (velocity of swimmer in river) and v_s=3m/s (velocity of swimmer in still water)

In case of shortest possible time, v=[v_sr²-v_s²]^1/2

Substituting the values,v=4m/s

Krish

6 Years ago

Velocity of swimmer w.r.t.river= Vsr=5

Velocity of swimmer w.r.t ground=Vsg=3

Vrg = X

5(5)-3(3)=X(X)

X=4

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A swimmer can swim in still water with a speed of 5m/s.While crossing a river his average speed is 3m/s.If he crosses the river in shortest possible time,what is speed of flow of water?

Savitri Yadav

3 Answers

sumanth

Vedant

Krish

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