Physics 5054 · O Level

The d.c. motor

15 practice questions on The d.c. motor, with worked solutions and instant marking.

A split-ring commutator is fitted in a simple d.c. motor. It changes the direction of the current in the coil. How many times does it reverse the current?

May/June 2016

The diagram shows a basic d.c. motor. The switch is switched on and the coil turns. Which change causes the coil to turn in the opposite direction and at a higher rate?

May/June 2016

What effect does a split-ring commutator have?

May/June 2017

Fig. 7.1 shows a section of a d.c. electric motor.

May/June 2017

In a simple motor, the coil is placed between the poles of a permanent magnet. If a current flows through the coil, it turns about its axis. What would reduce the frequency of rotation of the coil?

May/June 2019

Fig. 7.1 shows part of a simple d.c. electric motor. The motor is linked to a battery, and the battery's positive terminal is connected to terminal A.

May/June 2021

Fig. 5.1 depicts a basic d.c. motor fitted in a toy car.

May/June 2022

The diagram depicts a simple d.c. motor. What is the component marked Q?

May/June 2024

Students are required to propose factors that influence the rotational speed of a direct current (d.c.) motor. Three suggestions are given below. 1 the strength of the magnetic field 2 the current 3 the number of turns on the coil Which of these suggestions are correct?

May/June 2025

Fig. 7.1 depicts a basic d.c. motor. The poles at the ends of the magnets have not been labelled.

May/June 2025

The diagram illustrates a simple d.c. motor. What is the component marked Q?

Oct/Nov 2015

Which device is used to change electrical energy into kinetic energy?

Oct/Nov 2022

In a d.c. motor, the coil is linked to a commutator. As the commutator turns, it joins the coil to the power supply. After each half-turn, the current in the coil reverses. What is the commutator called, and what is the orientation of the plane of the coil at the moment the current reverses?

Oct/Nov 2023

What component of a simple d.c. motor reverses the current direction in the coil after each half-turn of the coil?

Oct/Nov 2024

Which part is not required for a simple d.c. motor to operate?

Oct/Nov 2025