Page 290 - Basic Electrical Engineering

phase as shown in Fig. 3.8 (a). Note that the magnitudes of voltage and
current may be different. In Fig. 3.8 (b) is shown current, i lagging the
voltage by 90°, i.e., by an angle π/2. The expressions for voltage and current

as shown in Fig. 3.8 (a) can be written as

Figure 3.8 Phase and phase difference between voltage and current

υ = V sin ωt
m

i = I sin(ωt + 0) = I sin ωt
m
m
The voltage and current shown in Fig. 3.8 (b) can be represented as

v = V sin ωt
m

i = I sin(ωt − π/2)
m