Two ships, A and B, leave port at the same time. Ship A travels northwest at 19 knots and ship B travels at 28 knots in a direction 40° west of south. (1 knot = 1 nautical mile per hour; see Appendix D.)(adsbygoogle = window.adsbygoogle || []).push({});

(a) What is the magnitude the velocity of ship A relative to B?

35.181 knots

(b) What is the direction of the velocity of ship A relative to B?

_____ ° east of north

(c) After what time will the ships be 110 nautical miles apart?

_____ h

(d) What will be the bearing of B (the direction of B's position) relative to A at that time?

_____° west of south

2. Vab = Vas - Vbs

Vas = -19cos45 + 19sin45 = -13.435i + 13.435j

Vbs = -28cos50 - 28sin50 = -17.998i - 21.449j

Vab = 4.563i + 34.884j

magnitude of Vab = 35.181

arctan(34.884/4.563) = 82.548 degrees

3. For some reason, this value for the angle (which I'm trying to find for part b) is wrong. Any ideas on what I did wrong guys?

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# Homework Help: Relative Motion of Ships

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