Relative velocity ship problem intuitively

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Homework Help Overview

The problem involves two ships, A and B, which are initially 4 km apart, with A moving eastward and B moving southward. The task is to determine the relative velocity of A with respect to B and the closest distance between the two ships during their motion.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • The original poster attempts to understand the intuitive reasoning behind calculating the closest distance between the two ships, expressing confusion about the second part of the problem. Some participants question the effectiveness of visual aids in conveying the problem setup.

Discussion Status

Participants are exploring the problem from different perspectives, particularly considering the reference frame of ship B to analyze the motion of ship A. There is no explicit consensus yet, but some guidance on using relative motion concepts has been suggested.

Contextual Notes

The original poster indicates a desire for a more intuitive understanding rather than a straightforward solution, highlighting a potential gap in their comprehension of the underlying concepts.

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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