Aircraft Speed with Wind: Calculating New Velocity

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To calculate the new speed of a jet airliner moving at 795 mph east with a wind blowing at 140 mph at 56 degrees north of east, vector addition is employed. The wind's velocity is broken down into its northward and eastward components using trigonometric functions. By adding these components to the aircraft's initial velocity, the new ground speed can be determined. Applying the Pythagorean theorem yields a new speed of approximately 855.14 mph. Thus, the aircraft's new speed with respect to the ground is around 855.14 mph.
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A jet airliner moving initially at 795 mph to the east where there is no wind moves into a region where the wind is blowing at 140 mph in a direction 56 degrees north of east. What is the new speed of the aircraft with respect to the ground? Answer in units of mph.

how can i start this off
 
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The first step would be to draw a vector diagram. Draw the normal cartesian coordinate system, assign the axes a direction (i.e. +y is north, -y is south, +x is east, -x is south). Since the plane relative to the air is traveling east at 795 mph draw a vector starting from the origin and going east (+x). Now draw the wind as a vector (starting from origin with an angle of 56 degrees from the +x axes). Now you have a vector diagram. That is the first step. Good Luck!
-HBar
 

To solve this problem, we can use vector addition to find the new velocity of the aircraft with respect to the ground. First, we can draw a diagram to represent the initial velocity of the aircraft (795 mph to the east) and the wind velocity (140 mph at 56 degrees north of east). From this diagram, we can see that the wind velocity can be broken down into two components: a northward component of 140*cos(56) mph and an eastward component of 140*sin(56) mph.

Next, we can add these components to the initial velocity of the aircraft to find the new velocity. We can do this by using the Pythagorean theorem: c^2 = a^2 + b^2, where c represents the magnitude of the new velocity, a represents the eastward component, and b represents the northward component.

Plugging in the values, we get c^2 = (795 + 140*sin(56))^2 + (140*cos(56))^2. Solving for c, we get c = √((795 + 140*sin(56))^2 + (140*cos(56))^2) = 855.14 mph.

Therefore, the new speed of the aircraft with respect to the ground is approximately 855.14 mph.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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