Electricity and magnetism — IGCSE Physics (0625) questions by topic

Which row describes the magnetic properties of soft iron and steel? soft iron steel --- --- --- A easy to demagnetise easy to demagnetise B easy to demagnetise hard to demagnetise…

Two charged rods, X and Y, are brought, in turn, near to a negatively charged rod. X is attracted by the negatively charged rod, and Y is repelled. What are the charges on X and…

The table gives data for four different electrical devices. Which device develops the greatest power? device voltage current --- --- --- --- A car headlight 12 V 3.0 A B cooling…

A mains-operated radio is a double-insulated appliance. Which statement is correct? A The radio does not need a neutral connection. B The radio must be earthed. C The radio…

Which statement describes a magnetic field? A It is a region where all objects experience a force. B It is a region where all electric charges experience a force. C It is a region…

A plastic rod is charged by friction. The plastic rod becomes positively charged. Which particles are transferred in this process? A atoms B electrons C protons D neutrons

A teacher makes a circuit using three 1.5 V cells and two 20 ohm resistors connected in series. The circuit diagram shows three cells in series in the top branch and two resistors…

A student investigates the turning effect on a current-carrying coil placed in a magnetic field. The student changes the current in the coil and the number of turns on the coil.…

There is a current of 3.0 A in a conductor. The current is changed to 6.0 A in the opposite direction. Which effect does this have on the magnetic field around the conductor? A It…

A student has a bar magnet and two metal blocks. The student places the bar magnet next to end W and end X of metal block 1. The student then places the bar magnet next to end Y…

A glass rod is rubbed with a silk cloth. The glass rod becomes positively charged. Which statement explains how this happens? A Negative charges move from the glass rod to the…

Which statement describes what is happening when there is an electric current in a metal wire? A Electrons in the wire vibrate. B Electrons move along the wire. C Positive charges…

Which two electrical quantities have the same unit? A current and charge B electromotive force (e.m.f.) and potential difference (p.d.) C potential difference (p.d.) and current D…

A 10 V d.c. power supply is connected across a resistor. The current in the resistor is 0.050 A. What is the resistance of the resistor? A 0.0050 ohm B 0.50 ohm C 2.0 ohm D 200 ohm

A resistor and a thermistor are connected in a series circuit, as shown. The circuit has a cell connected in series with an ammeter (A). A fixed resistor and a thermistor are…

In which circuit does the ammeter read 2.0 A? Each circuit is a series circuit containing a battery and two resistors in series with an ammeter (A). A: 12 V battery with two 6.0…

A 240 V mains-powered vacuum cleaner has a power output of 2700 W. Which fuse is suitable for use in the plug of the vacuum cleaner? A 3 A B 5 A C 10 A D 13 A

The transformer in a laptop power supply is used to change mains voltage from 240 V to 20 V. The transformer has 600 turns on the secondary coil. Which type of transformer is it…

A student has a bar magnet and two metal blocks. The student places the bar magnet next to end W and end X of metal block 1. The student then places the bar magnet next to end Y…

A glass rod is rubbed with a silk cloth. The glass rod becomes positively charged. Which statement explains how this happens? A Negative charges move from the glass rod to the…

Which statement describes what is happening when there is an electric current in a metal wire? A Electrons in the wire vibrate. B Electrons move along the wire. C Positive charges…

Which two electrical quantities have the same unit? A current and charge B electromotive force (e.m.f.) and potential difference (p.d.) C potential difference (p.d.) and current D…

A 10 V d.c. power supply is connected across a resistor. The current in the resistor is 0.050 A. What is the resistance of the resistor? A 0.0050 ohm B 0.50 ohm C 2.0 ohm D 200 ohm

A resistor and a thermistor are connected in a series circuit, as shown. The circuit diagram shows a cell, an ammeter (A) in series with a fixed resistor and a thermistor, and a…

In which circuit does the ammeter read 2.0 A? Four series circuits A-D are shown, each with two resistors and an ammeter: A: 12 V supply, two 6.0 ohm resistors in series. B: 12 V…

A 240 V mains-powered vacuum cleaner has a power output of 2700 W. Which fuse is suitable for use in the plug of the vacuum cleaner? A 3 A B 5 A C 10 A D 13 A

The transformer in a laptop power supply is used to change mains voltage from 240 V to 20 V. The transformer has 600 turns on the secondary coil. Which type of transformer is it…

The diagram shows a bracelet containing two magnets. The arrows represent the pattern and the direction of the magnetic field due to the magnets. The two magnets are at the ends J…

Which row describes an electric field and its direction? option description of electric field direction of electric field -------- --------------------------------…

Copper wire is available in fixed lengths but in various diameters d. Each wire has a different resistance R. Which relationship between R and d is correct? A R is directly…

The diagram shows three 20 ohm resistors, R1, R2 and R3, and a switch S connected to a d.c. power supply. R1 and R2 are connected in parallel with each other; the switch S can…

A wire connected to a resistor R is moved in a magnetic field. A current is induced in the direction shown. A magnet has its N pole on the left and S pole on the right, so the…

Which component is not found in an a.c. generator? A coil of wire B split-ring commutator C magnetic poles D slip rings

There is a current in a straight metal wire in the direction shown. The wire is vertical and the current is directed upwards (out toward the viewer looking from vertically above).…

A simple transformer contains an iron core. What is the function of the iron core in the transformer? A to conduct current from the primary coil to the secondary coil B to enable…

A positively charged balloon is placed against a wall. The charge makes the balloon stick to the wall. Which statement explains this? A Positive charges on the balloon attract…

A metallic wire X has a resistance. What is the difference in resistance for a wire of the same material as X that is: - shorter than X but the same diameter - the same length as…

The diagram shows the circuit for a potential divider. The diagram shows a cell connected to two resistors R1 and R2 in series. The potential difference across R1 is V1 and the…

A cell is connected to a parallel combination of a 2.0 ohm resistor and a 4.0 ohm resistor. The current in the 4.0 ohm resistor is 1.0 A. The diagram shows a cell connected to two…

When there is an electric current in a long straight wire, a magnetic field is created around the wire. Which diagram shows the correct pattern and direction of magnetic field…

The primary voltage supplied to a transformer is 3.0 V. The secondary voltage is 5.0 V and the secondary current is 2.0 A. The transformer is 100% efficient. What is the primary…

Which row describes the magnetic field around a weak magnet? direction of field spacing of field lines --- --- --- A north pole to south pole close together B north pole to south…

A 0.60 m length of resistance wire with a diameter of 0.25 mm has a resistance of 6.0 ohm. A second piece of resistance wire of the same material with a diameter of 0.50 mm also…

A circuit contains a cell with an electromotive force (e.m.f.) of 2.0 V. The current in the circuit is 2.0 A. How much energy is transferred by the cell in 2.0 minutes? A 2.0 J B…

What is the electromotive force (e.m.f.) of a cell? A the charge that passes through the cell per unit time B the energy supplied per unit charge as charge passes through the cell…

Four lamps and four switches are connected to a power supply, as shown. When all the switches are closed, all the lamps are lit. When one of the switches is then opened, only one…

In which mains electric wires are the fuse and the switch placed? fuse switch --- --- --- A earth live B live live C live neutral D neutral neutral

The diagram shows a wire moving downwards in a magnetic field between two magnetic poles (N pole on the left, S pole on the right, so the field points from N to S, i.e. from left…

When the generator shown rotates, there is an a.c. electromotive force (e.m.f.) across the resistor between points P and Q. Diagram 1 shows the position of the coil at time t = 0…

What is the purpose of the split-ring commutator in an electric motor? A to ensure that the magnetic field in the motor changes direction every half rotation B to ensure that the…

Fig. 8.1 shows the circuit diagram for a 16 ohm resistor and an 8.0 ohm resistor connected to a 6.0 V battery. Calculate the combined resistance of the two resistors shown in Fig.…

Fig. 9.1 shows a router. The router emits Wi-Fi signals. The power input to the router circuit is 9.0 W. The potential difference across the router circuit is 12 V. Calculate the…

Fig. 8.1 shows a mains-powered electric fan heater fixed on a bathroom wall. The pull cord switches the fan heater on and off. Suggest why a pull cord is safer than a push switch…

Fig. 9.1 shows two resistors, 20 Ω and 40 Ω, connected in series. Calculate the combined resistance of the two resistors in series.

Fig. 8.1 shows a mains-powered electric fan heater fixed on a bathroom wall. The pull cord switches the fan heater on and off. Suggest why a pull cord is safer than a push switch…

Fig. 9.1 shows two resistors, of resistance 20 Ω and 40 Ω, connected in series. Calculate the combined resistance of the two resistors in series.

Fig. 6.1 shows a person using a magnetic window cleaner. The part on the outside of the window is attracted to the inside part through the glass window. Each part of the window…

Fig. 7.1 shows a sketch of the current-voltage graph for an electrical component. The graph has current on the vertical axis and voltage on the horizontal axis, with the origin…

Fig. 8.1 shows a diagram of part of a simple a.c. generator. A U-shaped magnet surrounds a coil of wire wound on a soft-iron core (labelled C) mounted on an axle. The ends of the…

State what is meant by an electric field.

Fig. 8.1 shows a simplified diagram of an a.c. generator. A rectangular coil sits between the poles of a magnet (N pole on the left, S pole on the right) and rotates about a…

A student sets up the circuit shown in Fig. 7.1. Determine the value of the current measured by the ammeter.

State what is meant by an electric field.

Fig. 9.1 shows a transformer. It has a soft-iron core with a primary coil wound on one side and a secondary coil wound on the other side. There is an alternating current in the…

A student investigates the relationship between the diameter and the resistance of wires. The following apparatus is available: - wires with different diameters - instrument for…

A student investigates a light-dependent resistor (LDR). The student assembles a series circuit consisting of a power supply, a switch, a 470 ohm resistor and an LDR. Fig. 2.1…

Which diagram (A, B, C or D) shows the pattern and the direction of the magnetic field lines around a bar magnet? (A: N–S with field lines; B: N–S; C: S–N; D: S–N, each with…

Which material is a good electrical conductor? A glass B copper C rubber D wood

What is an electric current and how is an ammeter positioned in a circuit to measure the current in a resistor? A a flow of charge; in parallel with the resistor B a flow of…

Which unit is used for the potential difference (p.d.) between two points in an electrical circuit? A ampere (A) B joule (J) C ohm (Ω) D volt (V)

The circuit in the diagram contains four switches, S1, S2, S3 and S4, controlling a heater. Which three switches must be closed for the heater to work? A S1, S2 and S3 B S1, S2…

The metal case of an electrical appliance is fitted with an earth connection. What is the purpose of this? A to complete the circuit supplying the appliance so that it works B to…

A student moves a magnet into a coil. A voltmeter measures the magnitude of the electromotive force (e.m.f.) induced in the coil. Which quantity does not affect the magnitude of…

A student makes a small d.c. motor. The teacher supplies: battery, ammeter, voltmeter, coil of wire, magnets, resistor. The student may also use other equipment. Which equipment…

Small compasses are used to determine the direction of a magnetic field. Which diagram (A, B, C or D) shows the direction that the compass needles point when placed near the N and…

A metal bar is placed inside a current-carrying coil (diagram 1). With a small current in the coil, the bar holds a few nails (diagram 2). When there is no current, the nails drop…

There is a current I in a resistor of resistance R. The potential difference across the resistor is V. Which equation gives the power P dissipated by the resistor? A P = IR B P =…

A student tests the electrical conduction of four materials: aluminium, iron, plastic, silver. Which materials are good conductors of electricity? A aluminium, iron and silver B…

This question is about the potential difference (p.d.) across, and the current in, a variable resistor. The resistance of the variable resistor is increased. Which statement is…

Diagram 1 shows a resistor connected in a circuit. Diagram 2 shows an identical resistor connected in parallel with the first resistor. What is the combined resistance of the two…

Where must a fuse be connected in a mains electric circuit? A the earth wire only B the live wire only C the neutral wire only D the live wire and the earth wire

Which graph does not show the correct trend for the force F causing the turning effect on the coil in a d.c. motor? A F vs number of turns on the coil B F vs current C F vs…

The diagram shows part of the magnetic field between two bar magnets, with ends X and Y facing each other. (The field lines run from X to Y.) Which statement about the ends of the…

Diagrams 1, 2 and 3 show an experiment to compare two magnets 1 and 2 on a balance. A fixed magnet (N up, S down) sits on a balance reading 125.3 g alone. Magnet 1 (ends W and X)…

Which graph of voltage against time (A, B, C or D) shows an a.c. voltage? (The a.c. graph oscillates periodically above and below zero.)

There is a current I in a resistor for a time t. The potential difference across the resistor is V. What does the product IVt represent? A the charge flowing through the resistor…

A student designs a circuit to turn on a fan when the temperature increases. Which component (A, B, C or D) does the student need to use in her circuit? (The required component is…

Four statements about safety when designing electrical products are listed: 1 If the outer casing is a conductor, it should be earthed. 2 If the outer casing is a conductor, it…

A transformer has 400 turns on the primary coil connected to the 240 V mains supply. There are two secondary coils: coil 1 has 2500 turns and coil 2 has 20 turns. Which row is…

A class is designing a d.c. motor. To achieve a greater turning effect, three suggestions are made: 1 Have a larger current in the coil. 2 Have a stronger magnet. 3 Put a larger…

Which row describes suitable materials for use in a temporary magnet and in a permanent magnet? A temporary: soft iron; permanent: soft iron B temporary: soft iron; permanent:…

A magnetic field is represented in the diagram by magnetic field lines, with points A, B, C and D. At which point is the magnetic field strongest? (Where the field lines are…

When a conductor in a complete circuit cuts across a magnetic field, a current is induced in the conductor. Which statement about the induced current is correct? A The induced…

The diagram shows a solenoid carrying an electric current, with points X (inside the solenoid), Y (just outside one end) and Z (further away). Which row compares the magnetic…

A conducting wire is placed between the poles of a magnet (N on the left, S on the right). When the current is in the direction shown, the force on the wire acts out of the page.…

Which types of electric current are in the primary coil and the secondary coil of a step-up transformer? A primary a.c.; secondary a.c. B primary a.c.; secondary d.c. C primary…

Which statement about the direction of a magnetic field at a point is correct? A It is the direction of the force on an N pole placed at that point. B It is the direction of the…

A resistor transfers 100 J of energy when a charge of 10 C flows through it. What is the potential difference across the resistor? A 0.10 V B 10 V C 10 W D 1000 W

Wire X and wire Y are made from the same metal. Wire X: length 1.0 m, cross-sectional area 0.40 mm², resistance 2.0 Ω. Wire Y: length 1.3 m, cross-sectional area 0.30 mm². What is…

The diagram shows two resistors used as a potential divider across a 3.0 V supply: a 5.0 kΩ resistor and a resistor R in series, with a voltmeter across R reading 1.8 V. What is…

Two electrical appliances are connected to the mains. The cable to one includes an earth wire; the cable to the second does not need an earth wire. What is a reason for this…

The diagram shows a simple a.c. generator: a magnet rotates around a fixed coil on an iron core. The e.m.f. output is a sine wave. The magnet is shown at positions P, Q and R; the…

A 24 V power supply and a 100% efficient transformer are used to light a 6.0 V, 12 W lamp. What is the current in the power supply? A 0.50 A B 2.0 A C 3.0 A D 8.0 A

Two small compasses are placed close to a strong bar magnet (N at top, S at bottom). In which directions do the compass needles point (diagram A, B, C or D)? (The needles align…

Three statements about magnetic fields: 1 A magnetic field is described as a region in which a stationary electric charge experiences a force. 2 The direction of a magnetic field…

A student rubs a plastic rod with a cloth. The rod becomes electrically charged and is attracted by a negatively charged object. Which statement about the rod is correct? A It is…

Which circuit (A, B, C or D) shows the directions of the conventional current I and the flow of electrons? (Conventional current flows from + to −, electrons flow the opposite…

A cell has an electromotive force (e.m.f.) of 1.5 V. How much energy is transferred by the cell when it drives 6.0 C of charge round a complete circuit? A 4.0 J B 4.0 W C 9.0 J D…

A metal resistance wire of length l and cross-sectional area A has resistance R. What is the resistance of a metal wire of the same material that has length 2l and cross-sectional…

The diagram shows two circuits, each with a relay that is normally open when there is no current in the coil. Circuit 1 contains a temperature-sensing arrangement; circuit 2…

A transformer is 100% efficient. Which pair of equations are both valid for the transformer? A IpVp = IsVs AND Vp/Np = Vs/Ns B Vp/Ip = Vs/Is AND NpVp = NsVs C Vp/Ip = Vs/Is AND…

Fig. 8.1 shows an arrangement for making an electromagnet, consisting of a solenoid and a core, connected to a 12 V battery, a variable resistor, an ammeter A and a switch. The…

Fig. 9.1 shows the power cable for connecting a desktop computer to the mains electricity circuit. State the name of each of the three wires inside the power cable.

A battery, a lamp L, a fixed resistor R and a switch S are connected as shown in Fig. 7.1 (6.0 V battery; R in series, L in parallel with the branch containing S). The potential…

The battery in a laptop computer is connected to a battery charger for 20 minutes. The potential difference (p.d.) across the battery is 14 V. The current in the battery is 1.8 A.…

Fig. 9.1 shows an electricity cable that has a fault: the plastic insulation is damaged, exposing the copper wire. The cable is used for supplying electricity at a high voltage.…

Fig. 8.1 shows part of a circuit for measuring the resistance of a lamp (a battery, an ammeter A and a lamp). Draw on Fig. 8.1 to show how to connect a voltmeter to measure the…

Fig. 9.1 shows three devices: a compass (with compass needle), a transformer (with core and coils), and an electromagnet (with core). The main parts are labelled. Complete Table…

Fig. 6.1 shows an isolated metal sphere suspended by an insulating thread from the ceiling. The sphere is negatively charged. The charge on the sphere produces an electric field…

Fig. 7.1 shows three bars of steel, A, B and C. A student is given the three pieces. Two of the pieces are magnetised and one piece is unmagnetised. Describe and explain how the…

Fig. 8.1 shows a circuit designed to switch on a night light when the surroundings are dark, using a light-dependent resistor (LDR) and a light-emitting diode (LED). On Fig. 8.1,…

Fig. 7.1 shows two charged metal plates: a positively charged plate on top and a negatively charged plate below, with X at the centre of the space between them. On Fig. 7.1, draw…

Fig. 9.1 shows a mobile phone being charged on a wireless charging plate (a primary coil in the charging plate and a secondary coil in the mobile phone). When the charging plate…

A bar magnet is next to a steel bar. Some of the magnetic field lines due to the magnet are shown emerging from end X (field lines spread out from X) and going into end Y, with…

Which row about electrical conduction in metals is correct? (Columns: statement 1; statement 2.) A It is the movement of free electrons. Electric charge is a flow of current. B It…

The diagram shows three wires, P, Q and R. They are all made from the same metal. P has length 2 cm and cross-sectional area 0.8 cm²; Q has length 4 cm and cross-sectional area…

A 60 W lamp operates at normal brightness for 2.0 minutes. How much energy is transferred by the lamp? A 0.50 J B 30 J C 120 J D 7200 J

What is a thermistor? A a container to keep a hot liquid warm B a circuit to control room temperature C a temperature-dependent resistor D a heater for a room

The diagram shows a circuit containing two identical resistors connected to a battery. The current is measured at X (in the battery branch) and at Y (in the branch with the…

The mains voltage is 120 V. Which fuse should be fitted to an electric kettle with a power of 1.5 kW? A 3 A B 5 A C 10 A D 13 A

The diagrams show a strong magnet and a weak magnet moving into the same coil of wire at different speeds. Arrangement X: strong magnet moving slowly into the coil. Arrangement Y:…

The diagrams show a current-carrying wire with an arrow in the direction of the current. Which diagram shows the magnetic field produced by the current? Diagram A shows straight…

What are the best materials to use for the construction of a transformer? A copper for the core and steel for the coils wound around it B copper for the core and copper for the…

The diagram shows what happens when a bar PQ is brought near to a permanent magnet which is standing on a balance. With the magnet alone (S on top, N at bottom) the balance reads…

Direct current (d.c.) can be represented on a voltage–time graph. Which graph shows the correct waveform for a d.c. supply? A is a triangular (zig-zag) wave, B is a sinusoidal…

A resistor with a potential difference (p.d.) of 100 V across it carries a current of 5.0 mA. What is the resistance of the resistor? A 0.50 Ω B 20 Ω C 500 Ω D 20 000 Ω

The diagram shows the information label on an electric kettle: Voltage 110 V a.c., Power 1500 W, Frequency 50 Hz. What is the value of the current when the kettle is heating…

A student makes a battery by connecting five cells in series, as shown. The cells have e.m.f.s 2.5 V, 2.0 V, 1.5 V, 2.5 V and 2.0 V. What is the electromotive force (e.m.f.) of…

The diagram shows the safety label on an electric oven: 60 Hz, 240 V ~, 10.1 A. The oven is connected to a mains electric circuit. A fuse is placed in the circuit to protect the…

A straight wire is stationary between the poles of a magnet. It lies perpendicular to the magnetic field, passing between the two magnet poles of a C-shaped magnet. Which action…

The diagram shows a wire hanging vertically between the poles of a magnet (N on the left, S on the right). There is a current in the wire in the direction shown (upward). The wire…

The diagram shows three small compasses near a bar magnet. Compass P is above the magnet, compass R is below the magnet, and compass Q is beyond the S pole end. The bar magnet is…

A negatively charged rod is brought close to an isolated, uncharged metal sphere. The near side of the sphere is labelled P and the far side is labelled Q. What are the charges on…

The diagram shows a simple circuit with a cell, an ammeter A and a voltmeter V connected to measure across a length of wire. The ammeter reading is 2.0 A and the voltmeter reading…

A lamp is rated 240 V, 0.40 A. The lamp operates at normal brightness for 1.0 min. How much energy does the lamp transfer? A 60 J B 96 J C 600 J D 5800 J

The diagram shows a torch containing two cells, a switch and a lamp. Which circuit diagram is correct for the torch? A two cells in series with a switch and a lamp, all in a…

Which symbol represents a device that contains a current-carrying coil in a magnetic field? A a fuse / resistor box symbol B a motor symbol (circle with M) C a thermistor /…

The diagram shows a three-core cable connecting a three-pin socket to an electric fire with a metal frame. The earth, live and neutral connections of the socket are labelled E, L…

A student investigates electromagnetic induction. She moves the N pole of a magnet quickly towards a coil of wire. There is a reading on the sensitive voltmeter. What can she do…

The direction of the current in a straight wire X is into the paper. Which diagram shows the shape of the magnetic field pattern around the wire? A concentric circles around the…

What does a step-up transformer increase? A current B energy C power D voltage

The diagram shows part of the magnetic field around a strong magnet. Position A is just above the top edge near the pole, B is in a field-line region to the right, C is further…

There is a current of 0.60 A in a closed circuit. How much charge passes a point in the circuit in 2.5 min? A 0.24 C B 1.5 C C 90 C D 5400 C

Which two physical quantities have the unit J/C? A charge and energy B charge and potential difference (p.d.) C electromotive force (e.m.f.) and p.d. D e.m.f. and charge

A copper wire is placed in an electrical circuit and its resistance is measured. The wire is then replaced with a second copper wire with twice the length and a quarter of the…

Which circuit contains a diode connected in series with a fixed resistor? A a circuit with an LDR in series with a fixed resistor B a circuit with two variable resistors in series…

In the circuit shown, resistor X has twice the resistance of resistor Y. X and Y are connected in parallel across a cell. Which statement about the circuit is correct? A The…

A 4 Ω resistor and an 8 Ω resistor are connected in series with a power supply. A voltmeter connected across the 8 Ω resistor reads 36 V. What is the voltmeter reading when it is…

A metal rod, XY, is placed in a magnetic field so that it is perpendicular to the field, as shown. The field lines point to the right (from left to right across the page). In…

The diagram shows a basic electric motor: a rectangular coil between the poles of a magnet (N left, S right), labelled features X (the coil), Y and Z (at the connection/contacts)…

Two transformers, P and Q, each have 2000 turns on their primary coils and 1000 turns on their secondary coils. Both transformers are 100% efficient. The secondary of transformer…

The diagram shows the magnetic field around a conductor which is carrying a current into the paper, drawn as concentric circles. Points A, B, C, D lie below the conductor at…

A positive ion in a vacuum moves at a steady speed in a straight line. There is a potential difference between the two parallel metal plates P (top) and Q (bottom) so that they…

In the circuit shown, the voltmeter reads 2.0 V. A charge of 5.0 C passes through the resistor in a certain time. How much energy is supplied to the resistor in this time? A 0.40…

Which diagram shows the current-voltage (I-V) graph for a filament lamp? A a curve that flattens (gradient decreasing) as V increases B a straight line through the origin C a…

The diagram shows an electrical circuit: a cell connected to three parallel branches, each with an ammeter and a resistor (A₁ with 4 Ω, A₂ with 3 Ω, A₃ with 2 Ω). Which statement…

The diagram shows an arrangement of resistors in series and parallel: R₁ is in series with the parallel combination of R₂ and R₃. Which equation is used to calculate the combined…

An electrical engineer has made a pair of components P and Q. The resistance of P decreases as the temperature rises. The resistance of Q increases as the temperature rises. The…

The diagram shows a wire XY moving upwards in a magnetic field between the poles of a magnet (N pole on the left, S pole on the right; X at the bottom of the wire, Y at the top).…

Diagram 1 shows a magnet being pushed (N pole downward) into a coil connected to a centre-zero sensitive voltmeter, and the pointer deflects. Diagram 2 shows a stationary magnet…

What is the purpose of the brushes and the split-ring commutator in a d.c. motor? A to change the size of the current B to keep the coil turning in the same direction C to keep…

The diagram shows β-particles being directed (travelling to the right) between the poles of a magnet, with the N pole above and the S pole below the beam path. In which direction…

The diagram shows the magnetic field of a bar magnet (S on the left, N on the right). A dotted path PRQ runs over the top of the magnet from P (just above the N pole) over R…

The diagram shows a charged sphere and the direction of the electric field at point X due to the sphere (the field arrow at X points towards the sphere). An electron is placed at…

A battery moves 3.0 C of charge round a complete circuit. The battery transfers 12 J of energy during this process. What is the electromotive force (e.m.f.) of the cell? A 0.25 V…

A cylinder of conducting putty has length l, diameter d and resistance R. The putty is now moulded into a cylinder of diameter 2d that has the same volume. By which factor does…

A number of identical resistors of resistance 10 Ω are arranged in circuits. Which arrangement of resistors will give an overall resistance of 25 Ω? A one 10 Ω resistor in series…

The circuit diagram shows a thermistor in a potential divider. Two voltmeters X and Y are connected in the circuit: X reads the p.d. across the upper fixed resistor, Y reads the…

In an experiment, strong magnetic fields provide a force that keeps charged particles moving with a horizontal circular motion. Positive particles are accelerated clockwise when…

When there is a current in a solenoid, a magnetic field is formed around it. How does the magnetic field change if the current is increased (spacing of field lines; strength of…

The diagram shows the structure of a simple transformer with a primary coil and a secondary coil on a core. Which row shows the correct conditions for the efficiency of the…

A student tests various materials to determine whether they are electrical conductors or insulators. The student uses the circuit shown in Fig. 9.1 (a 6 V battery, a switch, a…

In an experiment, a student uses an electrical heater connected to a power supply. The current in the electrical heater is 2.2 A. The voltage (p.d.) across the heater is 12 V.…

Fig. 9.1 represents part of a d.c. electric motor. The coil of wire rotates at a steady speed between the N and S poles of a magnet, with the current direction shown. State two…

A student connects a circuit with two lamps and three switches, S1, S2 and S3, as shown in Fig. 8.1 (a 6.0 V supply, with S1 and S2 in series with one lamp branch, and S3…

Fig. 9.1 shows a magnet spinning steadily near to a coil. There is a reading on the voltmeter. Explain why there is a reading on the voltmeter.

A potential divider is made by connecting a light-dependent resistor (LDR) and a thermistor in series. Fig. 6.1 shows the potential divider, a voltmeter and a direct current…

A solid bar is inside a copper solenoid. Fig. 7.1 shows that the copper solenoid is connected in series with a battery and a variable resistor. The device shown in Fig. 7.1 is an…

Fig. 9.1 shows a wireless charging plate used to charge the battery in a mobile phone (cell phone). The coil of wire is part of an electric circuit. The charging plate is…

Fig. 5.1 shows a metal sphere S. The sphere has been charged with a negative charge. There is an electric field around sphere S. On Fig. 5.1, draw four field lines to show the…

A car windscreen is covered in condensation (small droplets of water). Thermal energy is used to remove the droplets of water. The thermal energy is provided by three resistors on…

Fig. 8.1 shows the magnetic field pattern around two permanent magnets placed on a card. The magnets are repelling each other. On Fig. 8.1, label both the poles on each magnet.

Fig. 9.1 shows a series circuit. Two of the components in the circuit are labelled: a power supply and a lamp. State the name of two other components in the circuit.

Fig. 10.1 shows an arrangement used to demonstrate electromagnetic induction: a permanent magnet (S pole then N pole) moving towards a coil of wire connected to a sensitive…

A student uses a permanent magnet to lift some unmagnetised nails. Some of the nails are made of iron and some are made of steel. Fig. 7.1 shows the magnet (N pole and S pole)…

A student uses the circuit in Fig. 8.1 to measure the resistance of the heater in the circuit (with a variable resistor and a heater). The symbols for the two meters in Fig. 8.1…

A student has a desktop computer that connects to the 240 V a.c. mains electrical supply (Fig. 9.1). The desktop computer has an on-off switch in one of the wires that connect it…

Fig. 8.1 shows the electrical symbols for some circuit components. Draw a line from each electrical symbol to the name of the circuit component it represents (names: fuse, lamp,…

Fig. 7.1 shows a circuit that contains a battery, a switch, a voltmeter and three 40 Ω resistors, R1, R2 and R3. The switch is open and resistors R1 and R2 form a potential…

The electricity supplied to a town is transmitted using a high-voltage cable. A transformer in the town has a soft-iron core. Explain the principle of operation of a simple…

State what is meant by a magnetic field.

An electric heater uses a resistance wire of resistance 26 Ω. The power dissipated in the resistance wire is 2500 W. Calculate the current in the resistance wire.

The voltage across the primary coil of a 100% efficient transformer is 220 V and the voltage across the secondary coil is 12 V. The current in the secondary coil is 2.5 A.…

A student investigates the change in resistance of a lamp filament when the current in the lamp is increased. The following apparatus is available: a power supply, a low-voltage…

A student investigates the change in current in a conducting liquid as the distance between two electrodes is changed. The circuit is shown in Fig. 4.1 (a power supply, an ammeter…

A student investigates the change in resistance of a lamp filament when the current in the lamp is increased. The following apparatus is available: a power supply, a low-voltage…

A student investigates the change in current in a conducting liquid as the distance between two electrodes is changed. The circuit is shown in Fig. 4.1 (a power supply, an ammeter…

A student investigates a circuit containing different combinations of resistors, using circuit A in Fig. 2.1 (not yet complete: resistor U in series with a 3 Ω resistor between…

Fig. 8.1 shows a solenoid (long coil of wire) connected in a circuit. When the switch is closed, there is a large current in the circuit. Describe an experiment to identify the…

A student investigates an electric circuit. Fig. 9.1 shows the student's circuit: a 6.0 V battery, a variable resistor, an ammeter (A) and a heater connected in series. Describe…

Fig. 9.1 shows an electric water heater connected to the mains electrical supply, with a plastic cover. Fig. 9.2 shows the electrical safety label for the heater: 230 V (volts),…

Different materials have differing magnetic properties. State the name of a material that is suitable for a temporary magnet.

Two identical resistors, R1 and R2, are connected to a 24 V battery, as shown in Fig. 7.1 (in series). The value of each resistor is 50 Ω. Calculate the combined resistance of R1…

Fig. 8.1 shows an arrangement for transmitting electricity generated by a power station. The power station generates electricity at 25 kV a.c. A step-up transformer raises this to…

Describe what is meant by alternating current (a.c.).

A plastic rod is uncharged. When the rod is rubbed with a woollen cloth, the rod becomes negatively charged. Explain, in terms of particles, why the rod becomes negatively charged.

A cylinder is made of modelling clay, which is an electrical conductor. Fig. 8.1 shows the cylinder (with a cross-sectional area and a length). The cylinder is connected into a…

Fig. 6.1 shows the circuit diagram for a flashlight (torch). The electromotive force (e.m.f.) of the battery is 4.5 V. The circuit contains a 60 Ω fixed resistor. The current in…

Fig. 7.1 shows the electric field pattern around point X (radial field lines), with a point Y nearby. On Fig. 7.1, draw an arrow to indicate the direction of the force on a…

Fig. 8.1 shows the single turn coil of a simple direct current (d.c.) motor placed between magnetic poles S (left) and N (right), with current flowing in the coil and an observer…