Answer: Vb is the vector (-5.37m/s, 8.59 m/s), with a module 10.13m/s
then the ratio Vb/Vr = 10.13m/s/5.37m/s = 1.9
Explanation:
We can use the notation (x, y) where the river flows in the x-axis and the pier is on the y-axis.
We have Vr = (5.37m/s, 0m/s)
Now, if the boat wants to move only along the y-axis (perpendicularly to the shore).
The velocity of the boat Vb will be:
Vb = (-c*sin(32). c*cos(32))
Then we should have that:
5.37 m/s - c*sin(32) = 0
c = (5.37/sin(32))m/s = 10.13 m/s
the velocity in the y-axis is:
10.13m/s*cos(32) = 8.59 m/s
So Vb = (-5.37m/s, 8.59 m/s)
the ratio Vb/Vr = 10.13m/s/5.37m/s = 1.9 where i used Vb as the module of the boat's velocity.
