Question

Question #b6919

Answer 1

The boat is moving at `20/sqrt(3) kph` or `11.54 kph`

Explanation:

We want the passenger to think that the boat is moving north, so we don't want the boat moving away or towards the passenger. So the velocity of the boat in the east direction has to be the same as the velocity of the ship in the east direction so the passenger doesn't see the boat get closer or farther away.

We have a triangle that looks like this

And we are solving for X .

We know that `cos(30) = 10/x`

Rearranging gives `x = 10/cos(30)`

So `x = 10/(sqrt(3)/2) = 20/sqrt(3)`

So the velocity of the boat is `11.54 kph` going 30 degrees to the east.