# angle of phase

Discussion in 'Homework Help' started by djstar, Apr 27, 2008.

1. ### djstar Thread Starter Active Member

Jan 26, 2008
39
0
could some one please give me a helping hand with this . a circuit consists of a 300 Ω resistor in series with a 3H coil and a 5μF capacitor. Determine the tangent of the angle of phase difference between the current and the applied emf when the frequency is

A) 50Hz
B) 25Hz

for the 50Hz circuit i have worked out the impedance as 319 ohms. But not sure if i need this?

2. ### mik3 Senior Member

Feb 4, 2008
4,846
69
For 50Hz:

impedance of L= j942.48 ohm

impedance of C= -j636.62 ohm

impedance of R= 300 ohm

Total impedance =300 + j942.48 - j636.62 =300 + j305.86

Convert in polar form : 428.43 |__45.55 degrees

if you assume the voltage to have an angle of 0 degrees then the current will lack the voltage by 45.55 degrees.

You say to find this 'the tangent of the angle of phase difference' : i guess is the tanget of 45.55 degrees which equals 1.019

Go on for the 25Hz