A swimmer wishes to swim directly across a river that has a current of 2.5m/s. He can swim 3.5m/s in a pool. Include a diagram.

a. Calculate the heading that the swimmer must use in order to swim directly across a river relative to the bank.
b. What is the ground speed (magnitude of ground velocity)?

1 answer

I assume you have drawn a diagram of the vectors involved.
If straight across is zero degrees, then he must swim upstream at an angle x such that
sinx = 2.5/3.5
the ground speed is 3.5 cosx