View Full Version : Please help; what this Question meaning
Amy 212
05-07-2008, 11:42 PM
I don’t understand how to solve this question -
“Find the sinusoid magnitude and phase “in degrees” at 0.5 ms for this
V(t)= 5 sin (2π * 500 t + π/4 ) [V]
Thanks alot ...
Amy212
arfeller
05-08-2008, 01:36 AM
I don’t understand how to solve this question -
“Find the sinusoid magnitude and phase “in degrees” at 0.5 ms for this
V(t)= 5 sin (2π * 500 t + π/4 ) [V]
Thanks alot ...
Amy212
Is that symbol after the "2?" and "?/4" PI?
And can we assume the units of t is seconds?
jimbo
05-08-2008, 06:13 AM
This is a straight forward solution. You just don't have all the information.
I don't specifically recognize or remember that equation from my electrical/electronic school days. But it would make sense if your "n" was pi. You have given t as 0.5 ms, so all you need to plug in a value for V and git'r'done.
Mikey
05-08-2008, 08:27 AM
The formula as given is a little confusing, what with that [V] term dangling out there. If we assume t in seconds, and [V] just some arbitrary constant, you could express your answer in terms of [V]. All you really have to do is find the value of the sine function for t=.0005 seconds, which turns out to be .707. Thus the answer would be 3.535[V], but again I have no idea how to interpret the [V] term...
For t=.0005, the argument of the sine function evaluates to 0.5pi + pi/4 = 3*pi/4. Since 2pi radians = 360 degrees, the phase is 135 degrees. This is consistent with the value of the sine function, 0.707, which is the value of a sine function at any multiple of 45 degrees.
Was [V] originally written as |V|, by any chance? That would make sense.
Amy 212
05-08-2008, 11:14 AM
Hi guys;
I sorry;
V(t)= 5 sin (2pi * 500 t + pi/4 ) [V]
My problem i do not understand what "magnitude" mean?
And thanks again.
Mikey
05-08-2008, 02:13 PM
Magnitude would be the value of the function. For example, the magnitude (value) of a sine wave can be anything from -1 to +1. In my answer above, the magnitude of the function V(t) for t=.0005 was 3.535.