The longer the cable run, the ______ voltage loss there is.

The longer the cable run, the ______ voltage loss there is.

• A. More
• B. Less
• C. The same
• D. Unknown

Answer: (A)

Voltage drop is caused by the resistance of the conductor, and resistance increases with length. The drop for a current I is V_drop = I × R, and R grows in proportion to how long the wire is (R = ρL/A). So, as the cable run gets longer, the resistance grows and the voltage drop becomes larger for the same current. That’s why a longer cable run results in more voltage loss. To keep voltage loss down, you can use a wire with a larger cross-section, reduce the current, or increase the supply voltage to compensate.

Voltage drop is caused by the resistance of the conductor, and resistance increases with length. The drop for a current I is V_drop = I × R, and R grows in proportion to how long the wire is (R = ρL/A). So, as the cable run gets longer, the resistance grows and the voltage drop becomes larger for the same current. That’s why a longer cable run results in more voltage loss. To keep voltage loss down, you can use a wire with a larger cross-section, reduce the current, or increase the supply voltage to compensate.