106yes u can.
if u move perpendicular to river velocity, u will definitely reach the other side but not exactly opposite
62as ashish said.. u can cross it .. but will never reach the opposite (exactly!) bank...
does anyone wants to prove? (Not at all difficult!)
1yah why not..may b he will take a long distance n will flow down the river if he tries to cross horizontally...but due to vector addition atleast der will b a small component..that will help him cross d veryy fast flowing river.....
1sinθ is never greater than one ... so if the speed of the river is more than that of the man in still water, he can't make it directly opposite right?
1
RAY
·2008-12-15 08:45:15
suppose in the above case man has a velocity v........he make an angle @ [@=alpha]
his velocity along y axis will b vsin@.....as sin @ varies between 1 and -1...so mans velocity will b between his velocity v and -v...
and since the velocity of river is more than his velocity so the net resultant along y axis will b downward...so he will have to move down....
he cannot have velocity v and -v ofcorz as that will make component along the x-axis 0...so he will fail to cross the river to direct opposite bank......
1
RAY
·2008-12-15 08:46:15
that means even if mans velocity is equal to river..even then he cannot cross........rit bro???
62
Lokesh Verma
·2008-12-15 08:47:08
dont conuse crossing the river to reaching the exactly opposite bank!
1
varun
·2008-12-15 08:48:33
the man can always cross the river but he can't reach the exact opposite bank if r ≥ m where r is speed of river and m is speed of man in still water
1
RAY
·2008-12-15 08:49:06
yah sorry!!that will b cross to directly opposite bank......[:)]
1sry due to some connection probs i couldnt join
but
d=vmcosQ*t
so t=d/vmcosQ
also drift x=(vr-vmsinQ)*t=(vr-vmsinQ)*d/vmcosQ
if Q=0
x=vr*d/vm
for vr>vm
x>d
possible!!!!!!!!!!
so y cant it exactly reach
sry for image