A boat leaves the harbor entrance and travels 28 miles in the direction N 43° E. The captain then turns the boat 90° and travels another 15 miles in the direction S 47° E. At that time, how far is the boat from the harbor entrance, and what is the bearing of the boat from the harbor entrance?

Step-by-step explanation:

A boat leaves the harbor entrance and travels 28 miles in the direction N 43° E.

Displacement in vector form

= 28 cos43 i + 28sin43j

= 20.47 i + 19.1 j

The captain then turns the boat 90° and travels another 15 miles in the direction S 47° E

Displacement

= 15 cos47 i - 15 sin47 j

= 10.22 i - 10.97 j

Total displacement

= 20.47 i + 19.1 j + 10.22 i - 10.97 j

= 30.69 i - 8.13 j

Magnitude of displacement

= 31.75 miles

Angle with east direction

TanФ = - 8.13 / 30.69

Ф = 15 degree south of east.