Voltage Drop Formula and Sample Sums

Voltage Drop Formula :

Voltage Drop Formula V(v) in volts is equal to the current I(A) in Ampere and multiply the impedance Z(ohm) in ohm. Hence the Voltage Drop Formula can be written as

V(v)=I(A)* Z(ohm)


I→ current in amperes

Z→ impedance in ohm

Sample Sums :

Sums 1:

Calculate the voltage drop across the circuit? In a current of 8A flows through a circuit that carries a resistance of 30 Ω.

Solution :


Current I=8A

Impedance z=30 Ω

The voltage drop formula is given by




Example 2 :

Calculate the voltage drop? In a lamp of 10 Ω and 20 Ω are connected in series. A current of 5 A is made to flow through it.

Solution :

Resistance z=(10+20) Ω

Z=30 Ω

Current I=5A

The voltage drop formula is given by



Leave a Comment