電路中的能量與電壓：練習題

Two identical resistors are connected in parallel to a battery. If the voltage across the battery is \(V\) and the current leaving the battery is \(I\), which statement is correct regarding the voltage and current for each resistor?

A specific component is placed in a circuit. When the intensity of light falling on the component increases, the current in the circuit is observed to increase. Identify the component and explain the change in its resistance.

A lamp is connected to a power supply with a potential difference of \(12 \text{ V}\). A current of \(0.50 \text{ A}\) flows through the lamp for \(2.0 \text{ minutes}\). Calculate the total energy transferred to the lamp.

State the relationship between energy transferred, charge, and voltage, and define what a volt is in terms of energy and charge.

A charge of \(30 \text{ C}\) flows through a filament bulb in \(2 \text{ minutes}\). If the potential difference across the bulb is \(6 \text{ V}\), calculate the total energy transferred during this time.

Explain why the total resistance of a circuit decreases when a second resistor is added in parallel to an existing resistor.

Domestic lighting systems are usually connected in parallel circuits rather than series circuits.
(a) Provide two reasons why a parallel circuit is more appropriate for lighting in a house.
(b) State what happens to the total resistance of the circuit when an additional lamp is switched on in parallel.

An electrical component in a circuit has a potential difference of \(9.0 \text{ V}\) across it and a steady current of \(0.20 \text{ A}\) flowing through it.
(a) Calculate the total electrical charge that passes through the component if it is left on for \(5.0 \text{ minutes}\).
(b) Determine the total energy transferred to the component during this time interval.