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Ship A is located at 4 km north and 2.5 km east of ship B. Ship A has a velocity of 22 km/h toward the south, and ship B has a velocity of 40 km/h in a direction 37 degrees north of east. (a) What is the velocity of A relative to B in unit-vector notation with i toward the east? (b) Write an expression (in terms of i and j) for the position of A relative to B as a function of t, where t=0 when the ships are in the positions described above. (c) At what time is the separation between the ships least? (d) What is that least separation?
i,j are unit vectors.
vPA=VPB+VBA
Angles are in degrees
(a)
dr/dtA= -22km/h j
dr/dtB= 40cos(37)i+40sin(37)j
dr/dtBA= -40cos(37)i-22km/h j-40sin(37)j
(b)
[itex]\int[/itex]drBA=[itex]\int[/itex]-40cos(37)i-(22km/h+40sin(37))j dt
rBA=(2.5-40cos(37)t)i+(4-t(22+40sin37))j
(c)
Now I don't know how to solve it lol
(d)
I'm really lost on how you can solve the minimum distance or the time when it reaches the minimum distance.
Please give me at least a hint
Homework Equations
i,j are unit vectors.
vPA=VPB+VBA
The Attempt at a Solution
Angles are in degrees
(a)
dr/dtA= -22km/h j
dr/dtB= 40cos(37)i+40sin(37)j
dr/dtBA= -40cos(37)i-22km/h j-40sin(37)j
(b)
[itex]\int[/itex]drBA=[itex]\int[/itex]-40cos(37)i-(22km/h+40sin(37))j dt
rBA=(2.5-40cos(37)t)i+(4-t(22+40sin37))j
(c)
Now I don't know how to solve it lol
(d)
I'm really lost on how you can solve the minimum distance or the time when it reaches the minimum distance.
Please give me at least a hint
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