Voltage drop can be calculated using Ohm's law.

• A. True
• B. False
• C. Only for AC
• D. Only for capacitors

Answer: (A)

Voltage drop is governed by how much current is flowing and how much opposition the element offers. Ohm’s law directly ties these ideas together: for a resistor, the voltage drop V equals the current I through it times its resistance R. In AC contexts, this generalizes to V = I·Z, where Z is impedance that combines resistance and reactance. The drop’s magnitude is |V| = |I|·|Z|, though the voltage and current may be out of phase if reactive elements are involved. So you can calculate voltage drop using Ohm’s law for any linear element in both DC and AC circuits. It isn’t limited to AC or to capacitors, and it doesn’t apply to nonlinear components that don’t follow Ohm’s law.