Submitted by Orman Language School team:

Ingy Ashraf Mohamed Mostafa
Mona Wafaay Mohamed
Ziad Ibrahim Abdelfattah

Sponsor and Project Supervisor:

Dr. Nasr Zeinhom
Professor at the Faculty of Engineering
Matareyya - Helwan University

Introduction

An Electric Motor is a machine which converts electric energy into mechanical energy. Connecting electricity from a battery or a power source to a motor results in making the shaft start to spin around. There are motors which are powered by a DC (direct current) source such as a battery, and motors which are powered by an AC (alternating current) source. Although there are many designs of electric motors, the principle is the same.

Two related physical principles underlie the operation of motors. The first is the principle of electromagnetic induction discovered in 1831 by the British scientist and inventor Michael Lardy. It states that: if a conductor is moved through a magnetic field or if the strength of a magnetic field passing through a stationary conducting loop is made to vary, a current is set up or "induced" in the conductor. The second is the converse of this principle which is that of electromagnetic reaction, observed by the French physicist Ander Marie Ampere in 1820.

So, when you have an electric current carried through a conductor such as a length of copper wire placed in a magnetic field, this wire will experience a force. By winding the conductor with many coils in precise positions and electrical connections, the created force will make the coil turn. When the coil turns, the shaft of the motor will turn.

Parts of an Electric Motor

Motors consist of two basic units: the field, which is the electromagnet with its coils: and the armature, which is the structure supporting the conductors that cut the magnetic field and carry the exciting current in a motor

Field Trip

In order to get acquainted with the parts of the electric motor, we visited the workshops of the Faculty of Engineering, Matareyya, Helwan University. We saw a number of electric motors of different sizes and saw how they work. It was obvious that when electric energy is input to them, they produce kinetic energy (motion) that can be used to drive any machine.

We also saw electric generators and saw how their work is the opposite of electric motors, they convert kinetic energy to electric energy.

Components of the Electric Motor

1. A wooden box.
2. A key for switching ON and OFF.
3. Iron laminations isolated from one face
4. An electric spinner
5. A small fan for testing the motor
6. An electric wire and a plug

The motor was assembled on the wooden box as the photograph at the end of the report shows.

Testing the Motor

1. The plug was connected to the electric power AC source
2. The switch was switched ON.
3. The passage of current made the laminations an electromagnet
4. The electric spinner started to turn with the small fan.
5. Switching the current OFF stopped the motor.

Acknowledgment

We wish to thank Dr. Nasr Zeinhom - Professor at the Faculty of Engineering - Matareyya - Helwan University for his help and advice and for donating the parts that we have used in building the motor.

The Project Reviewers

Bernd Eggen, Amelia Irion, John Lovell, Brad Roscoe , Hossam El Badawy