Physics Paper Example: Factors That Affect the Strength of an Electromagnet

Electromagnets are simple devices that mimic the behavior of natural magnets however, electromagnets change their magnetic field strength, unlike natural magnets. This is accomplished by varying any of its four basic components. It is created using an electric current. Making electromagnets involves curling a wire into a series of turns that coil around a metallic core material. The core material is mostly made of a ferromagnetic material such as iron. Multiple turns of the wire strengthen and concentrate the magnetic field more than a single stretch of wire (Smith, Jjunju, Young, Taylor, & Maher, 2016). The electromagnetic field strength is stronger at the center of the coil while weaker around the exterior because the core metallic material amplifies the electric current. The principle of electromagnetism is applied in electric devices such as speakers, hard disks, generators and motors. In addition, an electromagnet has been of great significance in scrap yard as it is used to pick up heavy scrap metals that require recycling. MRI machines use electromagnetism to take photos of internal parts of the body through the utilization of magnets. the low-intensity non-ionizing electromagnetic fields have been used for the treatment of malaria and cancer (Lai & Singh, 2010).

The nature of the core material used as a component to make electromagnets affects its strength. Materials that are utilized as core are mostly metals. Different metals with same physical sizes have adverse effects on the strength of an electromagnet where some metals may make the electromagnet stronger while others make it weaker. Non-metals cannot be used as core materials since they do not conduct electricity. However, metals such as iron when used to make cores result in strong electromagnetic fields. When steel cores are used instead, electromagnetic fields become weaker. Neodymium cores make the strongest electromagnetic fields. The whole core material requires to be surrounded by the coil as slight sliding of the core material weaken the electromagnetic field since there is less of the metal that acts as a conductor is within it. The variations in the magnetic strength observed when different core materials are used are due to the different number of flux lines passing through the central core. Flux lines are easily created in materials that have high permeability thus improving the strength of the electromagnetic field, however, materials that have low permeability produces electromagnets whose fields are weak (Mahmood, 2015). The size of the core material is of great concern. This is because thicker core materials reduce electromagnetic field strength. Core materials that have hollows have been observed to increase electromagnetic strength.

The strength of the current passing through the metal core also affects the strength of the electromagnetic. The strength of the current flowing across the wire is determined by the source voltage. Therefore, changing the voltage will also change the field the electromagnet produces. A higher voltage from the battery translates to more current through the coil which in turn strengthens the electromagnetic field, however, low voltage results to less current flowing the coil leading to a weak electromagnetic field (Smith et al., 2016).

The number of turns and size of the wire on the core material also affects the strength of the electromagnetic field. Large size wires that are coiled on the core metal experience less current resistance. This will increase the current flowing through them, therefore, increasing the electromagnetic field strength. Thin wires wrapped around the metal core have high resistance on the current that flows through them leading to weak electromagnetic field strength. The nature of the wire also affects the strength of the electromagnetic field since they are made up of metals with different inherent resistance to current flow. The greater number of turns of the wire on the metal core make stronger electromagnetic fields, however, less number of loops on the metal core results to a weaker electromagnetic field. This is attributed to the fact that each loop creates something like a large bar magnet and therefore more loops will mean the creation of larger size bar magnet which has stronger electromagnetic fields.

Electromagnetic field strength is also affected by temperature. High temperature distorts the movement of electrons in a conductor increasing resistivity making the electromagnet lose its electromagnetic field strength because of the reduced current that passes through the conductor. The increased resistivity is due to vibration of atoms increasing the distance between magnetic domains resulting in reduced electromagnetic field strength. Moderate temperatures result in average electromagnetic field strengths because the magnetic domains are at a relative position to one another thus maintaining a particular electromagnetic strength. Nevertheless, colder temperatures increase the electromagnetic strength because of reduced resistivity of the conductor caused by magnetic dipoles that come close together (Yadav, 2016). The increased density increases the strength of the electromagnetic field.

In conclusion, an electromagnetic field strength is affected by the nature and sizes of materials that make it up. Other factors that greatly affect its strength are temperature and the strength of current that passes through the core. However, the effect of the strength of the current is directly influenced by the voltages from the source.

References

Lai, C. H., & Singh, P. N. (2010). Medical applications of electromagnetic fields. Earth and Environmental science.

Mahmood, J. B. (2015). Physics and electromagnetism. Bahru: International Association of Certified Practicing engineers.

Smith, R. T., Jjunju, F. P., Young, I. S., Taylor, S., & Maher, S. (2016). A physical model for low-frequency electromagnetic induction in the near field based on direct interaction between transmitter and receiver electrons. Proceedings A.

Yadav, A. (2016). Effect of Temperature on Electric Current, Magnets and Electromagnet . International Journal of Advancements in Technology.