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Physics · Unit 1 · Electrical circuits · Current, potential difference and energy flow

Explain that the energy inputs in a circuit equal the sum of energy output from loads in the circuit.

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Question 1

A circuit is constructed with a 12 V battery connected to three loads: a lamp rated at 6.0 W, a resistor dissipating 3.0 W, and a motor performing mechanical work at 2.5 W. The circuit also experiences 0.5 W of energy loss in the connecting wires. Which statement best explains the energy relationship in this circuit?

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Question 2

A 12 V battery supplies energy to a circuit containing three loads: a motor (6.0 J), a lamp (3.5 J) and a resistor (2.5 J). What key principle explains the relationship between the battery's energy input and the total energy dissipated by the loads?

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Question 3

In a circuit, a power supply delivers \(240 \text{ W}\) of electrical power. The circuit contains three resistive loads operating simultaneously. Which statement correctly describes the relationship between the power supplied and the power dissipated in the loads?

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