How to draw a phasor addition on AC circuit?

[maali5]

How to draw a phasor ?

Homework Statement

Two alternating currents are applied out of phase with each other. One is 4 volts and the other is 3 volts 27° out of phase.

These can be written as (4, 0°) and (3, 27°)

Homework Equations

a)draw both phasors
b)draw the combined phasor between (0 degree and 360 degree)
c)label peak voltage and state its value

The Attempt at a Solution

a)A rough drawing on paint http://imageshack.us/photo/my-images/3/plotb.jpg/

b) I know A= 6.8106 volts by using this formula

r=√a²+b²

r=3cos27 + 4i + i(3sin 27)

r=√(3cos27 + 9)² + (3sin27)²

=6.81v

angle=0.2014

 

[cepheid]

The drawing look OK, but I don't think you've got the right components. The real parts of the phasors are 4 and 3cos27 respectively. The imaginary parts are 0 and 3sin27 respectively.