Difficulty: Easy
Correct Answer: bleeder current
Explanation:
Introduction / Context:
A voltage divider is a simple network of resistors used to generate a stable, lower voltage from a higher supply. Even when no external circuit is connected to the divider's output node (that is, it is unloaded), current still flows through the series resistors. Knowing the correct terminology for this internal current is essential for power budgeting and understanding loading effects.
Given Data / Assumptions:
Concept / Approach:
With an unloaded divider, the current that flows from the supply through the series string returns to the supply without doing useful work for a load. This standing current is historically called the bleeder current. It sets the quiescent power dissipation of the divider and provides a defined output impedance. When a load is added, part of the current diverts into the load and the output voltage can sag depending on the divider's design.
Step-by-Step Solution:
Identify the current path: source → R1 → R2 (→ …) → source return.Compute magnitude if needed: I_bleeder = V_in / R_total (no load present).Recognize terminology: this standing current is widely termed “bleeder current.”Therefore, the correct name is bleeder current.
Verification / Alternative check:
Power supplies often include a permanent resistor from output to return called a bleeder to discharge capacitors and set a minimum load. Its current is likewise called bleeder current, matching the divider case.
Why Other Options Are Wrong:
Resistor current/divider feed current: informal or ambiguous terms; the standard term is bleeder current.
Load current: zero in an unloaded divider.
Voltage current: not a standard electrical term.
Common Pitfalls:
Underestimating bleeder power loss. The power wasted is P = I_bleeder^2 * R_total, which must be considered for efficiency and resistor wattage ratings.
Final Answer:
bleeder current
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