Quote:
Originally Posted by willwren
Quote:
Originally Posted by L27Buick
i cant read my formula in my notes on how to do this problem here is the problem
the peak voltage of a sine wave is 10v. what is its instantaneous value at 30 degrees and at 40 degrees?
anyone?

I'd have to pull my old college books out.....and I'm at work right now......I can give you a rough idea of what your answers would be:
At 0, 180 and 360, your instantaneous voltage is 0, right?
At 90° you're 10v peak (assuming 20v pp?), so at 30° you should be .3 of 10, or 3v. 40° would be 4v. Actually a pretty simple problem.

Doesn't quite work that way Bill...for pete'* sake you are a laser technician!
You are right on the quadrant angle values.
You have to know the cycle time to know the phase angle. The top (or bottom) of a sine wave is a parabola based on the amplitude and halfcycle time, therefor it is not a linear relationship for amplitude vs. angle.
Yes, I realize I am telling everything but how to find the answer. I would have to look it up either in a AC circuits or a trig textbook.
Jay