Page 337 - Basic Electrical Engineering

ii. Apparent power, S = V × I = 200 × 11.18 = 2.236 kVA
iii. Real power, P = V I Cos ϕ = V I = 200 × 5 = 1.0 kW
R
iv. Reactive power, Q = VI Sinϕ = V × I = 200 × 10 = 2.0 kVAR
L
Example 3.11 The parallel circuit shown in the Fig. 3.37 is connected

across a single-phase 100 V, 50 Hz ac supply. Calculate:

i. the branch currents
ii. the total current
iii. the supply power factor
iv. the active and reactive power supplied by the source.

Figure 3.37

Solution:

It is assumed that the students are aware of the method of representation of a
complex number in the forms of a + ib or a + jb. However, this has been

explained in the next section.