✴✴The instantaneous value✴✴
The instantaneous value of a sine wave is taking the ordinate at a given time.
An alternating voltage has the following expression
a(t)=A0sen (wt +b)
A0= Maximum Value
A=Value effective
w:= Pulsation (2pi f)
f= frequency
t=time
T= period
b= initial phase angle
example:
an AC voltage has the following instantaneous expression:
a(t)=12sen314t V.
to calculate the value of the voltage at 2.5 ms
e(2.5ms) 12sen(314 rad/s 2.5 10-3s)= 12sen(0.785 rad) = 8.5 v
In sexagesimal degrees
0,785 rad = 45°
e(2,5ms) 12 sen(45°) = 8.5 v
the value of e at 30°
e=12 sen 30° = 6 v
