Answer:w = 74.66 mph
d = 19.92 degrees
Explanation:
Let's call the speed of the wind "w" and the direction angle of the wind "d". We can use vector addition to solve for these unknowns.
First, let's find the direction of the plane. The bearing of N * 65 deg * E can be represented as a vector with an initial point at the North pole and a terminal point 65 degrees east of due north. Since the plane is flying on this bearing, its direction vector is the same as the bearing vector. We can find the components of this vector as follows:
cos(65) = x / 1
x = cos(65)
y = sin(65)
So the direction vector of the plane is <cos(65), sin(65)>.
Next, let's find the ground speed vector. We can represent this vector as the sum of the plane's airspeed vector and the wind vector:
ground speed = airspeed + wind speed
We know that the magnitude of the ground speed vector is 390 mph, and we know the direction angle of the ground speed vector is 30 degrees. We can use this information to set up two equations:
|airspeed + wind speed| = 390
tan(d) = (wind speed)_y / (wind speed)_x
Since we know the direction vector of the plane, we can express the airspeed vector in terms of this vector as follows:
airspeed = 360 <cos(65), sin(65)>
Now we can substitute the airspeed vector and the wind speed vector into the equation for the ground speed vector, and use the fact that the magnitude of the ground speed vector is 390 to solve for the components of the wind speed vector:
|360 <cos(65), sin(65)> + <(wind speed)_x, (wind speed)_y>| = 390
Squaring both sides and using the fact that cos^2(x) + sin^2(x) = 1, we get:
129600 cos^2(65) + 129600 sin^2(65) + 720(wind speed)_x cos(65) + 720(wind speed)_y sin(65) + (wind speed)_x^2 + (wind speed)_y^2 = 152100
Simplifying, we get:
51840 + 720(wind speed)_x cos(65) + 720(wind speed)_y sin(65) + (wind speed)_x^2 + (wind speed)_y^2 = 152100
Substituting the equation for the direction angle of the wind and simplifying, we get:
51840 + 720w cos(65 - d) + w^2 = 152100 tan^2(d)
We now have two equations and two unknowns: w and d. We can solve for them using algebra or a numerical solver. Using a numerical solver, we find:
w = 74.66 mph
d = 19.92 degrees
Therefore, the speed of the wind is 74.66 mph, and its direction angle is 19.92 degrees.