Impedance, Reactance, Resistance

[m4tty]

Hi,

I was just wondering if anyone out there could explain how to calculate the impedance of a circuit containing combinations of the above. For example

Series Circuit containing 6 Ohms resistance and 8 Ohms Capacitive Reactance. Calculate impedence??

Thanks in advance.

Matt

 

[ezzzekiel]

er cant draw out the formula but will try

Z (total im) = root squared of Rsquared + Xc squared

if inuctance was in circuit it would be deducted from Xc or vice versa

 

[offshorealex]

from distant memory... I think that impedance (z) is equal to the square root of (resistance (r) squared plus reactance (x) squared

 

[Jurasic Spark]

Treat it as a right angled triangle (Pythagoras)
Impedance (Z) is the hypotenuse.
Resistance is the adjacent.
Reactance is the opposite.......where you have Xc and XL one leads and the other one lags so the resultant (one take away the other) is the value you use as per Mr Pythagoras' theorem.

You can then find youe Power Factor with cos, ADJ/HYP

 

[pushrod]

you will find in most of these questions involving pythagoras that they give you it will be a 3,4, 5 triangle (or multiple of eg 6,8,10 or 30 40 50 etc etc) the hypotenuse being the impedance. If you remember that it will help you to quickly check answers

So in your example above 2 of the sides are 6 and 8 so the hypotenuse/impedance is 10 ohms.

[or the square root 6^2 + 8^2 = 10]