0
$\begingroup$

So I have been out of school for a very long time and have a forehead slapping question:

$ m = \tan(\theta) $ where $ \theta $ is an angle, but all that gives me is $ \frac yx $.

I need to know how far something should move in each vector given that it is pointed at a certain angle.

How is this determined?

  • 0
    Seems to work for some angles. I may be looking at a software bug2019-01-11

1 Answers 1

1

Let's say a point moved for point $(x_1, y_1)$ to $(x_2, y_2)$ , then we know the point has moved $ x_2 - x_1 $ along x-axis and $ y_2 - y_1 $ along y-axis.

Given than a point moves $ R $ distance along $ \theta $ direction, let, $ \Delta x $ and $ \Delta y $ be the distance moved forward simultaneously on x-axis and y-axis, then we know, $ \Delta x = R \frac {\Delta x}{ R } \text{ ,but } \frac {\Delta x}{ R } = \cos \theta \text{ so we have } \Delta x = R \cos \theta $

And similarly $ \Delta y = R \sin \theta $ enter image description here

  • 0
    This works, of course, I had a rounding issue and needed to convert to radians.2012-06-12