IGCSE Physics Electricity & Magnetism MCQs (2026 CH)

A wire is moved across a magnetic field. This causes an induced current in the wire. The induced current interacts with the magnetic field to produce a force on the wire. In which direction is this force?

• in the direction of the current
• in the direction of movement of the wire
• in the opposite direction to the current
• in the opposite direction to the movement of the wire

The diagram shows a circuit which includes two resistors and a battery. The voltmeter reads 6.0V. What is the potential difference across the 30Ω resistor?

• 2.0V
• 6.0V
• 18V
• 24V

A resistor has a potential difference (p.d.) of 12 V across it and a current of 0.60 A in it. What is the resistance of the resistor?

• 0.050 ohm
• 2.0 ohms
• 7.2 ohms
• 20 ohms

There is a current I in a resistor of resistance R for a time t. The potential difference (p.d.) across the resistor is V. Which equation gives the power P dissipated in the resistor?

• P=IR
• P=It
• P=IV
• P=IV/t

Which metal could be used for a permanent magnet and which metal could be used for the core of an electromagnet?

• Permanent magnet: iron; core of electromagnet: copper
• Permanent magnet: iron; core of electromagnet: steel
• Permanent magnet: steel; core of electromagnet: copper
• Permanent magnet: steel; core of electromagnet: iron

Two resistors, with resistances R1 and R2, are used as a potential divider. What is the relationship between R1, R2 and potential differences V1 and V2?

• R1 x R2 = V1 x V2
• R1 x V1 = R2 x V2
• R1/R2 = V1 x V2
• R1/R2 = V1/V2

A student designs a circuit to use as a dimmer switch for a lamp. What happens to the brightness of the lamp and the potential difference (p.d.) across the lamp, when the slider is moved from X to Y?

• Brightness of lamp: decreases / p.d. Across the lamp: decreases
• Brightness of lamp: decreases / p.d. Across the lamp: increases
• Brightness of lamp: increases / p.d. Across the lamp: decreases
• Brightness of lamp: increases / p.d. Across the lamp: increases

A resistor R is connected in parallel with an 8.0Ω resistor. The resistance of this combination is 4.0Ω. What is the resistance of resistor R?

• 0.50Ω
• 2.0Ω
• 4.0Ω
• 8.0Ω

The diagram shows an a.c. generator. With the coil in the position shown, the output voltage is +10 V. When does the output voltage become –10 V?

• When the coil has turned 90°
• When the coil has turned 180°
• When the coil has turned 270°
• When the coil has turned 360°

What is an electric field?

• A region around a wire carrying an electric current in which a compass needle experiences a force
• A region in which an electric charge experiences a force
• A region in which an electric charge is attracted by the Earth’s gravity
• A region through which electromagnetic radiation is passing