Question

. A boat is travelling on a bearing of 25° east of north at a speed of 5 knots (a
knot is 1.852 km/h). After travelling for 3 hours, the boat heading is changed
to 180° and it travels for a further 2 hours at 5 knots. What is the boat’s
bearing from its original position?

Answer 1

Just draw a diagram and lay out the vectors.

Start at (0,0)
In 3 hours it has gone 3*1.852km at N 25° E.

So, at that point, its position is (5.55 sin 25°, 5.55 cos 25°) = (2.348,5.035)

Now, it travels 1.852*2 km at S, for another displacement of (0,-3.704)

Its final position is thus (2.348,1.331), which is 3.248km at E 29.5° N (or, N 60.5° E) from (0,0)

Answer 2

If the following forces are applied to a body, what additional force is
required to keep the body in balance:
50 N acting 40° east of north
30 N acting east
60 N acting 20° north of west
15 N acting south