Question

2 ships X&Y are traveling in different directions at equal speed. the actual direction of motion of X is due North but to an observer on Y the apparent direction of motion of X is north east. the actual direction of motion of Y as observed from shore is?

options..
a) east b) West c) south east d) south west

Answer 1

Let, Velocity of ship `X` is `Vx`,that of `Y` is `Vy` and velocity of Ship `X` w.r.t `Y` is `Vxy`

So, `Vxy = Vx-Vy=Vx+(-Vy)`

Now,given, `Vx= Vy`

And, angle between `Vxy` and `Vx` is `45` degrees

So, if the angle between, `Vx` and `-Vy` is `theta`

`theta = 90` degrees ( as two vectors of same magnitude when act at 90 degrees,their resultant makes 45 degrees with each of them)

So, `-Vy` is directed along east,hence `Vy` is directed along West