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rishiraj20006
Nov11-06, 12:32 AM
Frendz , here is a problem of motion in 2 dimensions. I simply stuck in basics .

A man wants to cross a river 100mt long He has a velocity of 10m/s in still water and river has a velocity of 20m/s. What angle should he make with flow of river so that displacement from where he started initially should be minimum?

I guess some concept of maximum and minimum will be used here but I don’t know how to apply

TheloniousMONK
Nov11-06, 02:07 AM
Think of this in terms of vectors. I think the question is asking for the man's down-river vecocity to be 0 and his velocity across the river to be a maximum. Let us know if you need further assistance.

QuantumCrash
Nov11-06, 02:52 AM
No need to shout. This is not a projectile question but instead a vector question. Resolve the rivers vectors horizontally and vertically first.