Relative velocity ship problem intuitively

AI Thread Summary
Two ships, A and B, are 4 km apart, with A moving east at 8 km/hr and B south at 6 km/hr. The problem requires calculating the magnitude of A's velocity relative to B and the closest distance between the two ships. The relative velocity can be determined using vector components, leading to an angle calculation that helps find the closest approach. The closest distance is calculated as 2.4 km, derived from the sine of the angle formed by their velocities. Understanding the problem intuitively involves analyzing A's motion from B's reference frame to determine when they are nearest to each other.
anurag07
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Homework Statement


Two ships A and B are 4 km apart. A is due west of B. If A moves with uniform velocity of 8 km/hr due east and B moves with a uniform velocity of 6 km/hr due south. Calculate 1) the magnitudeof the velocity of A in relation to B 2) the closest distance apart of A and B

Homework Equations


The first solution is pretty simple but the second one, I don't get it. I know how to just solve it but without any intuition. Can someone help me get an intuitive idea of the solution of 2) ? The solution will be down there.

The Attempt at a Solution


In the example BD is drawn from B to relative velocity of A with respect to B represented by AE. From the given distance between A and B is 4km i.e. AB = 4km. In ABE sin x = BE/AE = 6/10 ( x= Angle EAB, BE = Velocity of B in opposite direction, AE = relative velocity of A in respect to B )
x=36.67
Closest distance apart from A to B is BD.
Now in BDA,
BD = sin x * AB = sin 36.87 * 4 = 2.4 km
This is the closest distance.
 

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Posting tiny sideways pics is not a good way to get people to look at them.
 
phinds said:
Posting tiny sideways pics is not a good way to get people to look at them.
Dont have a good phone. Sorry. And vertical pictures are even tinier.
 
The idea is to use B's reference frame. In that frame, what are the NS and EW components of A's motion. At what point does B perceive A as being at closest approach?
 
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