Skip to main content
Ch 26: Direct-Current Circuits
Chapter 26, Problem 26

A triangular array of resistors is shown in Fig. E26.5. A circuit diagram showing resistors of 18.0 Ω, 22.0 Ω, and 13.0 Ω arranged in a loop.
What current will this array draw from a 35.0-V battery having negligible internal resistance if we connect it across (b) bc?

Verified step by step guidance
1
Identify the resistors in the circuit and their values: 18.0 Ω, 22.0 Ω, and 13.0 Ω.
Determine the equivalent resistance of the resistors in series. Since all resistors are in series, the equivalent resistance (R_eq) is the sum of all resistances: R_eq = 18.0 Ω + 22.0 Ω + 13.0 Ω.
Calculate the total equivalent resistance: R_eq = 53.0 Ω.
Use Ohm's Law to find the current (I) drawn from the battery. Ohm's Law states that V = IR, where V is the voltage, I is the current, and R is the resistance.
Rearrange Ohm's Law to solve for the current: I = V / R_eq. Substitute the given values: I = 35.0 V / 53.0 Ω.

Verified Solution

Video duration:
6m
This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Ohm's Law

Ohm's Law states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) of the conductor. This relationship is expressed mathematically as I = V/R. Understanding this law is crucial for analyzing circuits, as it allows us to calculate the current based on the voltage supplied and the total resistance in the circuit.
Recommended video:
Guided course
03:07
Resistance and Ohm's Law

Series and Parallel Resistor Configurations

Resistors can be arranged in series or parallel configurations, affecting the total resistance in a circuit. In a series configuration, the total resistance is the sum of individual resistances (R_total = R1 + R2 + ...). In a parallel configuration, the total resistance can be calculated using the formula 1/R_total = 1/R1 + 1/R2 + ... This distinction is essential for determining how the resistors in the triangular array will influence the overall current drawn from the battery.
Recommended video:
Guided course
12:42
Combining Resistors in Series & Parallel

Equivalent Resistance

The equivalent resistance of a circuit is a single resistance that can replace a combination of resistors while maintaining the same current and voltage characteristics. For the triangular array of resistors, calculating the equivalent resistance is necessary to simplify the circuit analysis. This allows us to apply Ohm's Law effectively to find the current drawn from the battery when connected across specific points in the circuit.
Recommended video:
Guided course
03:44
Find Equivalent Capacitance #1