EEE/ETI 1202
CIRCUITS & NETWORK THEORY I
LECTURE 8
, Series A.C. Circuits
• An a.c. circuit differs from a d.c. circuit in many respects.
• First, in a d.c. circuit we consider resistances only whereas in an a.c. circuit, in
addition to resistance (R), inductance (L) and capacitance (C) also play the part.
• The elements L and C offer opposition (i.e. XL and XC) to current flow in an a.c
circuit.
• Secondly, the magnitude of current in an a.c. circuit is affected by the supply
frequency because XL (=2πfL) and XC (=1/2πfC) are frequency dependent
However, such a situation is not encountered in a d.c. circuit.
,
CIRCUITS & NETWORK THEORY I
LECTURE 8
, Series A.C. Circuits
• An a.c. circuit differs from a d.c. circuit in many respects.
• First, in a d.c. circuit we consider resistances only whereas in an a.c. circuit, in
addition to resistance (R), inductance (L) and capacitance (C) also play the part.
• The elements L and C offer opposition (i.e. XL and XC) to current flow in an a.c
circuit.
• Secondly, the magnitude of current in an a.c. circuit is affected by the supply
frequency because XL (=2πfL) and XC (=1/2πfC) are frequency dependent
However, such a situation is not encountered in a d.c. circuit.
,
