Oversimplified Vector Calculus Problem

XYZeagle
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I'm not asking for a solution to this problem. I'm just wondering about its validity.

Homework Statement



The wind velocity v1 is 40mph from east to west while an airplane travels with air speed v2 of 100mph due north. The speed of the airplane relative to the ground is the vector sum v1 + v2.


I completely disagree that the speed of the plane relative to the ground is the vector sum v1 + v2. The speed of the object would be changed by a force predicted by the drag equation. It's velocity also is also not constant with time.
 
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Presumably the airspeed takes drag into effect. As far as velocity being constant in time, here you are arguing with information given in the problem. The wind and plane speeds are given as constant in this problem. Choosing to not accept the given hypotheses is really not an option.
 
Mark44 said:
Presumably the airspeed takes drag into effect. As far as velocity being constant in time, here you are arguing with information given in the problem. The wind and plane speeds are given as constant in this problem. Choosing to not accept the given hypotheses is really not an option.

You know the speed of the plane before it encounters wind and the speed of the wind. The drag force caused by the wind will accelerate the plane, thus the changing velocity of the plane over time.
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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