Relative Velocity of Ship A to Ship B: Magnitude and Time

AI Thread Summary
The relative velocity of Ship A to Ship B is calculated to have a magnitude of 3.97 m/s and a direction of 40.01° north of east. This was determined using the Pythagorean theorem and trigonometric functions based on their respective velocities and directions. To find the time until the ships are 140 meters apart, the formula d = rt was applied, resulting in a time of approximately 35.26 seconds. This indicates that after 35.26 seconds, the two ships will be 140 meters apart. The calculations confirm the accuracy of the velocity and time estimates.
Clari
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Ship A travels at 3m/s due NE, ship B travels at 2.6 m/s in direction S30E.
a. What are the magnitude and direction of the velocity of ship A relative to ship B?
b. After what time will they be 140m apart?

I have found the answer to be 4.45m/s
But I don't know whether it is true...and I am not sure of its direction.
Please help. :frown:
 
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Clari said:
Ship A travels at 3m/s due NE, ship B travels at 2.6 m/s in direction S30E.
a. What are the magnitude and direction of the velocity of ship A relative to ship B?
b. After what time will they be 140m apart?

I have found the answer to be 4.45m/s
But I don't know whether it is true...and I am not sure of its direction.
Please help. :frown:

you can use the components of that vector you figured out to get the direction.
 
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a. The magnitude of the velocity of ship A relative to ship B can be calculated using the Pythagorean theorem:

V = √(3² + 2.6²) = √(9 + 6.76) = √15.76 = 3.97 m/s

The direction can be found using trigonometric functions:

tanθ = 2.6/3 = 0.8667

θ = tan⁻¹(0.8667) = 40.01°

Therefore, the velocity of ship A relative to ship B has a magnitude of 3.97 m/s and a direction of 40.01° N of E.

b. To find the time it takes for the ships to be 140m apart, we can use the formula:

d = rt

140 = (3.97)t

t = 140/3.97 = 35.26 seconds

Therefore, after 35.26 seconds, ship A and ship B will be 140m apart.
 
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