the table below shows the values of the resistance, capcitive reactance and inductive reactance for five RCL circuits. in which circuit will the voltage lead the current?
Resistance capacitive inductive
reactance reactance
a)50 ohm 288ohm 244ohm
b)120 ohm 58 ohm 18 ohm
c)212ohm 314ohm 78 ohm
d)30 ohm 219 ohm 180 ohm
e)150 ohm 79 ohm 212ohm
Current lags voltage (and voltage leads current) when the inductive reactance is greater than the capacitive reactance.
That is only the case in one of your five options
To determine in which circuit the voltage will lead the current, we need to compare the values of capacitive reactance and inductive reactance.
In an RCL circuit, the current leads the voltage when the capacitive reactance is greater than the inductive reactance. On the other hand, the voltage leads the current when the inductive reactance is greater than the capacitive reactance.
Let's analyze the values given in the table:
a) Resistance: 50 ohm, Capacitive reactance: 288 ohm, Inductive reactance: 244 ohm
b) Resistance: 120 ohm, Capacitive reactance: 58 ohm, Inductive reactance: 18 ohm
c) Resistance: 212 ohm, Capacitive reactance: 314 ohm, Inductive reactance: 78 ohm
d) Resistance: 30 ohm, Capacitive reactance: 219 ohm, Inductive reactance: 180 ohm
e) Resistance: 150 ohm, Capacitive reactance: 79 ohm, Inductive reactance: 212 ohm
Comparing the values, it appears that in the circuit with resistance 30 ohm, capacitive reactance 219 ohm, and inductive reactance 180 ohm, the inductive reactance is greater than the capacitive reactance. Therefore, in this circuit, the voltage will lead the current.
Hence, the correct answer is (d) 30 ohm, 219 ohm, 180 ohm.