A boat leaves point P on one side of a river bank and travels with constant

Question

velocity V in a direction towars point Q on the other side of the river directly
oposite P and distance D from it If r is the instantaneous distance from Q to the boat,
θ is the angle between r, and PQ, and the river travel with speed v, prove that the path of the boat
is given by
r=D*sec(θ)/(sec(θ)+tan(θ))^(V/v)

P
...................
|.
| .
| . --> v
D X
| .
| .
| .
|θ . V
| .
..................
¨ Q

Murray Spiegel 1.144

Answer 1

Hmmm, looks like an 8.01 problem

Answer 2

Hi juanpro is there other classical mechanic. I might want to join too.