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Ch 28: Fundamentals of Circuits
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796당신이 사용하는 게 아니라요?교과서 변경
28장, 문제 43

You have a 2.0 Ω resistor, a 3.0 Ω resistor, a 6.0 Ω resistor, and a 6.0 V battery. Draw a diagram of a circuit in which all three resistors are used and the battery delivers 9.0 W of power.

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Step 1: Recall the formula for power delivered by a battery: \( P = \frac{V^2}{R_{eq}} \), where \( P \) is the power, \( V \) is the voltage of the battery, and \( R_{eq} \) is the equivalent resistance of the circuit. Rearrange this formula to find \( R_{eq} \): \( R_{eq} = \frac{V^2}{P} \). Substitute \( V = 6.0 \ \text{V} \) and \( P = 9.0 \ \text{W} \) to calculate \( R_{eq} \).
Step 2: Once \( R_{eq} \) is determined, consider how the three resistors (2.0 Ω, 3.0 Ω, and 6.0 Ω) can be arranged to achieve this equivalent resistance. Recall the formulas for resistors in series \( R_{eq} = R_1 + R_2 + R_3 \) and in parallel \( \frac{1}{R_{eq}} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} \).
Step 3: Experiment with different combinations of series and parallel arrangements to match the calculated \( R_{eq} \). For example, you might try combining two resistors in parallel and then adding the third in series, or vice versa. Use the formulas for series and parallel resistances to verify the equivalent resistance for each configuration.
Step 4: Once the correct arrangement is identified, draw the circuit diagram. Ensure that the battery (6.0 V) is connected to the resistors in the configuration that achieves the desired \( R_{eq} \). Label the resistors and their values (2.0 Ω, 3.0 Ω, and 6.0 Ω) clearly in the diagram.
Step 5: Double-check your work by recalculating the total power delivered by the battery using \( P = \frac{V^2}{R_{eq}} \) with the equivalent resistance from your chosen configuration. Confirm that the power matches the given value of 9.0 W.

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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

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 by the formula V = IR, which is fundamental for analyzing electrical circuits and determining how voltage, current, and resistance interact.
추천 영상:
가이드 코스
03:07
Resistance and Ohm's Law

Power in Electrical Circuits

The power (P) delivered by an electrical circuit is defined as the rate at which energy is consumed or converted. It can be calculated using the formula P = IV, where I is the current and V is the voltage. Additionally, using Ohm's Law, power can also be expressed as P = I²R or P = V²/R, which helps in understanding how different components in a circuit affect overall power consumption.
추천 영상:
가이드 코스
06:18
Power in Circuits

Series and Parallel Circuits

In electrical circuits, resistors can be arranged in series or parallel configurations. In a series circuit, the total resistance is the sum of individual resistances, while in a parallel circuit, the total resistance is found using the reciprocal formula. Understanding these configurations is crucial for calculating the total resistance and current in the circuit, which directly impacts the power delivered by the battery.
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가이드 코스
09:51
Combining Capacitors in Series & Parallel
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