Select the width of the river (10 to 80 m), the distance downstream you wish to land (10 to 60 m, red mark shows position), the velocity of the boat (2 to 10 m/s) and the velocity of the current (East).Press Submit each time.
The red line represents the resultant velocity vector i.e. the actual path taken by the boat (blue).
Press First Angle and, when finished, Second Angle.
N.B.The green line represents the direction of the velocity of the boat.
Calculate the two angles (from left side of starting position) and corresponding times.
To check your results press the Answers button.
Press Reset to repeat the simulation with different values. N.B. Some combinations give impossible negative angles. Use:width:30, dist. down:40, Vb:4, Vc:5 OR width:66, dist. down:45, Vb:5.5, Vc:6.5