What Is the Speed and Angle of Raindrops in Different Reference Frames?

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SUMMARY

The discussion focuses on determining the speed and angle of raindrops relative to the ground based on observations made while driving north and south at 25 m/s during a rainstorm. When driving north, the rain appears at a 38-degree angle from the vertical, while it falls straight down when driving south. The equations used include V = vy + vx and V' = VR - V, where VR represents the velocity of the rain. The solution involves analyzing the components of the rain's velocity in different reference frames.

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Homework Statement



While driving north at 25 during a rainstorm you notice that the rain makes an angle of 38 with the vertical. While driving back home moments later at the same speed but in the opposite direction, you see that the rain is falling straight down.
a)From these observations, determine the speed of the raindrops relative to the ground.
b)From these observations, determine the angle of the raindrops relative to the ground.


Homework Equations



V=vy+vx
V'=VR-V

Where VR is the velocity of the rain



The Attempt at a Solution



When driving north I got

V=(-vRsinθR)i + (-vRcosθR)j

Using

V'=VR-V

I get V'=VR-V(-vRsinθR-25)i + (-vRcosθR)j




Im not sure how to set it up for going south. Any suggestions?
Would it look like this? V'=0i+ (-vRcosθR)j
?
And to find θ, would i use [ v'x / v'y}tan-1?


I thinks mostly all the subscripts and whatnot that's messing me up.
Thanks in advance for any help given :)
 
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Think of the three reference frames in this problem of interest. At rest relative to earth, moving away from home in the car, moving towards home in the car. In each reference frame the rain will be falling at a different angle. See,



Good luck!
 

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