Voltage drop across a component is caused by what?

Voltage drop across a component is caused by what?

• A. The magnetic field around the conductor
• B. The current flowing through a resistor
• C. The supply voltage
• D. The resistance value

Answer: (B)

The voltage drop across a resistor comes from the current flowing through it. Ohm’s law states V = I × R, so the drop across the component is determined by the amount of current and the resistor’s value. When current passes through, energy is dissipated as heat and a voltage difference appears across the component. The supply voltage is what drives that current, but the drop you measure across the resistor itself is caused by the current through it (scaled by its resistance). The magnetic field around a conductor isn’t what creates the resistor’s voltage drop, and the drop isn’t set by the supply voltage alone or by resistance alone without current.

The voltage drop across a resistor comes from the current flowing through it. Ohm’s law states V = I × R, so the drop across the component is determined by the amount of current and the resistor’s value. When current passes through, energy is dissipated as heat and a voltage difference appears across the component. The supply voltage is what drives that current, but the drop you measure across the resistor itself is caused by the current through it (scaled by its resistance). The magnetic field around a conductor isn’t what creates the resistor’s voltage drop, and the drop isn’t set by the supply voltage alone or by resistance alone without current.