# Obtaining the absolute velocity of a moving train based on angle of raindrops with respect to vertical axis

The problem is in the files attached.

I have been given the coordinates of the raindrops both start and end.
My question is how do I obtain the angle, and after that how do I arrange the equation to get Vtrain.

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• Thank you Philip, is ThetaWind always 30 degrees? I still dont quite get how to obtain the angle from the coordinates I was given. However everything you explained makes sense now.

• In general ThetaWind may not be 30 degrees, but in your problem it is assumed to be 30 degrees.

• Oh okay, so if I understand the assignment the first step in finding Vtrain should be to find the angle of the raindrop vectors using the coordinates that I was given? Should I do that using the slope?

• Yes.

• Great, thank you for the help Philip :),

• Sorry for asking again Philip, but how would I obtain Vtrain with respect to a fixed refrence, so the absolute velocity of the train?