Physics 5054 · O Level
Electromotive force and potential difference
37 practice questions on Electromotive force and potential difference, with worked solutions and instant marking.
In what other form can one volt be written?
May/June 2016
In what other form can one volt be written?
May/June 2016
The diagram represents a battery made from three $1.5\ \text{V}$ cells. What advantage does this cell arrangement have?
May/June 2016
A student links a battery to two resistors. The circuit diagram appears in Fig. 10.1. The potential difference (p.d.) across the 40 Ω resistor is 9.6 V.
May/June 2018
Which unit is equivalent to a volt?
May/June 2019
Fig. 7.1 illustrates two circuit components: a thermistor and an LDR. Fig. 7.2 presents a battery connected to a diode, an ammeter and a resistor. Fig. 7.3 gives the current-voltage graph for the diode.
May/June 2021
A student is studying how the potential difference (p.d.) $V$ across a fixed resistor $R$ varies when extra resistance is introduced into the circuit.
May/June 2021
A camera flash is operated, and a charge of $1.5\,\text{C}$ passes through the flash lamp in $0.0030\,\text{s}$. The mean voltage across the flash lamp is $3600\,\text{V}$. Calculate the electrical energy supplied to the flash lamp and the mean power supplied.
May/June 2022
Which unit is used for potential difference (p.d.), and what instrument is used to measure p.d.?
May/June 2022
A charge of $0.40\,\text{C}$ flows through a resistor in $1.0\,\text{s}$. Over $2.0\,\text{s}$, the resistor produces $20\,\text{J}$ of thermal energy. What is the potential difference across the resistor?
May/June 2022
When a camera flash is used, a charge of $1.5\,\text{C}$ passes for $0.0030\,\text{s}$ through the flash lamp. The mean voltage across the flash lamp is $3600\,\text{V}$. Calculate the electrical energy delivered to the flash lamp and the average power delivered.
May/June 2022
The diagram shows a battery made from three $1.5\,\text{V}$ cells. What is one advantage of arranging the cells like this?
May/June 2023
A potential difference of $4.0\,\text{V}$ causes a current of $3.0\,\text{A}$ to flow through a resistor. How much energy is transferred into thermal energy in $10\,\text{s}$?
May/June 2024
Which equation is correct for potential difference (p.d.)?
May/June 2024
A quantity is described as the work carried out by a source to move unit charge all the way around a complete circuit. Name the quantity and state its unit.
May/June 2025
A student sets up the circuit shown. The switch $S$ is then closed. What does the voltmeter read?
May/June 2025
Which physical quantity results from multiplying a charge by a potential difference (p.d.)?
Oct/Nov 2015
Which particles come from the hot filament of a cathode-ray oscilloscope (c.r.o.), and what type of field is used to speed them up?
Oct/Nov 2015
What does electromotive force (e.m.f.) mean?
Oct/Nov 2017
A battery in a circuit has two identical cells arranged in parallel. Which row states how currents $I_1$ and $I_2$ are related and gives the electromotive force (e.m.f.) of the battery?
Oct/Nov 2017
A $6.0\,\text{V}$ battery, three resistors, and three voltmeters are arranged in the circuit diagram shown. Voltmeter 1 shows $2.0\,\text{V}$. What are the readings on voltmeter 2 and voltmeter 3?
Oct/Nov 2017
A circuit battery is made up of two identical cells arranged in parallel. Which row states the connection between currents $I_1$ and $I_2$ and gives the electromotive force (e.m.f.) of the battery?
Oct/Nov 2017
A battery with electromotive force (e.m.f.) $10\,\text{V}$ is connected to a resistor. A charge of $2.0\,\text{C}$ travels through the resistor. How much work is done as the charge moves through the resistor?
Oct/Nov 2018
Which cable carries electrical energy at the highest voltage?
Oct/Nov 2018
What quantity is stored in a battery, and what unit is used for it?
Oct/Nov 2020
A sheet ripped from an exercise book is displayed. “_____ is the amount of work done (measured in joules) on one unit of charge (measured in coulombs) as it travels round the circuit.” What quantity is being defined?
Oct/Nov 2021
The diagram depicts a circuit that includes a $5.0\,\text{V}$ power supply, three resistors and four output terminals P, Q, R and S. Across which pair of terminals is the potential difference $1.5\,\text{V}$?
Oct/Nov 2021
The quantities X and Y are measured in the same unit, Z. X is the energy dissipated by a battery when it drives unit charge around the whole circuit. Y is the work done in a component when it drives unit charge through the component. What are X, Y and Z?
Oct/Nov 2021
Fig. 6.1 shows a circuit made up of a battery with electromotive force (e.m.f.) $4.5\,\text{V}$, a $28\,\Omega$ resistor, and a variable resistor.
Oct/Nov 2021
Which equation represents the electromotive force (e.m.f.) of a battery?
Oct/Nov 2022
The circuit’s power supply is formed from several cells, all with the same electromotive force (e.m.f.), and the cells are connected in parallel.
Oct/Nov 2022
An electric motor carries a current of $2.0\,\text{A}$. In $5.0\,\text{s}$, it transfers $20\,\text{J}$ of energy. What is the potential difference (p.d.) across the motor?
Oct/Nov 2023
A student investigates how the potential difference $V$ across the terminals of a power supply changes when the current $I$ in a circuit changes. Fig. 3.1 shows the circuit.
Oct/Nov 2023
Which quantity is defined as the electrical work performed by a source in taking a unit charge around one complete circuit?
Oct/Nov 2024
Four $1.5\,\text{V}$ cells are arranged in a circuit as shown. The switch is then closed. What reading does the voltmeter show?
Oct/Nov 2024
In what other form can one volt be expressed?
Oct/Nov 2024
A resistor with resistance $R$ is connected in a circuit with a variable resistor, a voltmeter and a power supply with electromotive force (e.m.f.) $E$. The resistance of the variable resistor rises from $0$ to $2R$. What change occurs in the voltmeter reading?
Oct/Nov 2025