A ship is heading due north at 20 km/h but is blown off courseby the wind which is blowing from 30° west of south at 5km/h:What is the speed of the ship, and in which direction is ittravelling?(Ignore the effects of tides or currents.)First steps of solution:Let us add the two vectors head to tail:Now, convert from polar to Cartesian:Ship's Vector:• x = r × cos(θ) = 20 × cos(90°) = 20 × 0 = 0• y = r × sin(θ) = 20 × sin(90°) = 20 × 1 = 20Wind's Vector:• x = r × cos(θ) = 5 × cos(60°) = 5 × 0.5 = 2.5• y = r × sin(θ) = 5 × sin(60°) = 5 × 0.8660 =4.330Now it is easy to add them:(0, 20) + (2.5, 4.330) = (2.5, 24.330)
Convert to Polar Form for final answer.
If the movement is counterclockwise subtract the angle from 90degrees. Clockwise and Counterclockwise are determined from 0degrees (East) on the compass, not 90 degrees (North) on thecompass.
Enter the direction (angle measurement) and velocity for thefinal answer.
A ship is heading due north at 20 km/h but is blown off course by the wind which is blowing from 30° west of south at 5
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