MAGNETISM AND ELECTROMAGNETISM

Magnetism and Electromagnetism

Magnetism and Electromagnetism

Introduction

I start the introduction with a question: Will increasing current in an electromagnet increase the power of the electromagnet? The electromagnet we will be making is a very primitive one compared to that of the complexity of modern electromagnets found in machinery, but the way it works is almost identical. Electromagnetic technology is extremely complex and because it is an electromagnet, the higher the current, the stronger it becomes, and with this an electromagnet can become incomprehensively strong.

Background information

When an insulated wire is wrapped around some form of iron, nickel or cobalt core, whether it be a nail or a u-shaped core, and then attached to a power supply it creates an electromagnet capable of picking anything from the size of a paperclip right up to anything as big as a car and bigger! Obviously such a primitive electromagnet would not be able to lift a car but a more advanced one would have no problem lifting a car. When the power supply is cut off the items picked up will fall off. This is because the current creates a magnetic field and this magnetic field is lost when it is turned off (Becker et al, 1985).

When a current channels through an electromagnet a magnetic field is produced. This field is built up in a series of concentric rings. The diagram below shows a cross-section of a wire's magnetic field. As you come further away from the wire the field weakens and spreads further apart from each ring (Carmi, 2002).

There are four main factors that affect the strength and size of this field (Rankin, 2003):

Current/voltage

Number of coils

Size and shape of core

Material of core (iron being the strongest)

The experiment in hand is simple. A piece of wire will be wrapped around an iron nail or some form of iron-based core where each end of the wire is attached to a circuit consisting of a power source and an ammeter. Our group will be testing the power of the magnet varying the power of the current around the circuit. We will be testing the strength from 0 to 5 amps (Fleisher, 2001).

My prediction is that when the current is increased in turn so does the strength of the electromagnet. I believe this because an electromagnet needs an electrical input in order to create a magnet, so logically if that electrical input is increased then it becomes ...