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Homework Statement
Homework Equations
Momentum conservation and Energy conservation equations
The Attempt at a Solution
Ok First I translated the units, ##1000 \frac {kg} {min}=16.66\frac {kg} {s}##
##10\frac {km} {h}=2.77\frac {m} {s}##
##20\frac {km} {h}=5.55\frac {m} {s}##
Now I tried to write an momentum equation for a barge which has small speed (##2.77\frac {m} {s}##,lets call it A)
İnitial momentum is ##p_i=Mv## final momentum will be ##(M-dm)(v+dv)##.
so ##Mv=(M-dm)(v+dv)## or I write ##Mv=(M-dm)v+Fdt##
I wrote like this cause İnitial momentum is ##Mv## that's for sure.After time Our mass decreases by ##dm## and our speed must increase by ##dv## for momentum conservation.
Actually I am stucked here.I couldn't write a proper equation.If Its true and I continue I get this (For both equations). The questions says last and inital velocity must be same so...thats why v are same
## \frac {dm} {dt}.v=F##
which gives me ##46N## which answer is "none"
interesting thing is the answer for fast barge is ##46N## so where I did wrong ??
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