Category Archives: Physics

use of electricity and magnetism in our future transportation

The Use of Electricity and Magnetism in Transportation

The Use of Electricity and Magnetism in Transportation


The use of electricity and magnetism in our future transportation has formed a subject of debate and research for many decades. As early as 1840s, the first linear motors were developed. A breakthrough in this technology was achieved in 1935 when the first practical linear motors were developed in Germany (Kirkland, 2007). Linear motors are important in enhancing magnetic levitation in modern high speed trains or what is referred to as Maglev trains. This essay will first analyze how the Maglev trains work and then explore how the concept can be applied for future transportation not only in trains but also in road systems.

Magnetic levitation has generated a lot of interest among many countries. In this system, electromagnets are used to create strong magnetic fields. The strong magnetic fields levitate the maglev trains above the track. This is in accordance to the magnetic principle which states that the like poles of a magnet repel each other while the unlike poles attract (Kirkland, 2007). The major components used in the maglev system include a source of power, guidance magnets and metal coils that run along the entire tracks.  The metal coils can be compared to the normal electric motors, except that in the case of maglev system, the motor is linear and extends the entire length of the tracks. Maglev trains are different from electric trains in that they do not have axles or wheels. In addition, they do not use motors for propulsion.


The entire track of the maglev system comprises magnetized coils which provide propulsion as well as levitation.  When alternating current passes through the magnetized coils, strong electromagnetic fields are created. Since the alternating current frequently reverses direction, the magnetized coils constantly change their polarity. These create push and pull forces that act behind the train and in front respectively, resulting from the magnetic fields. These forces keep the levitated train moving at high speeds of up to 300 miles per hour. The guidance coils are used to ensure that the train is always centered and hence difficult to go off the tracks. Reversing electric current in the tracks enables the train to slow down, stop, or even move in the opposite direction. Passengers are able to enjoy comfortable rides in such trains. With the introduction of computer controlled maglev systems, high speed trains are considered among the safest in the world.

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The use of electricity and magnetism has an advantage over other ways in that it eliminates the force of friction commonly encountered by the wheel and axle type of trains that are powered by fossil fuels (Brandon, 2013). The force of friction occurs when two bodies rub each other. Although friction keeps the train on track by enhancing the much needed grip between the wheels and the rails, the force tends to reduce motion. More power must thus be injected to overcome the force of friction which leads to fuel wastage. Maglev trains levitate on their tracks due to strong magnetic fields eliminating the force of friction. This is because they balance on air as they move at high speeds due to the strong magnetic force which overcomes the gravitational force (Brandon, 2013).

The technology involved in magnetic levitation is achieved by use of electric current and magnetism. One of the benefits in using this type of technology over traditional fuel-based technologies is that it is environmentally friendly. As earlier mentioned, maglev uses magnetism and electricity as the core sources of power. A maglev transportation system can thereby reduce pollution significantly. All over the world, traffic jams have become a huge menace especially in major cities. Traffic jams are a major cause of pollution in addition to increasing commuter time. A maglev system can significantly reduce the number of vehicles on roads and thus reduce environmental pollution. The maglev transportation system has already been implemented in some parts of the world such as Japan, China and Germany. Researchers assert that the maglev transportation system is socially, economically and environmentally sustainable, and thus the key to our future transportation (Gross, 2013).

The maglev transportation system is environmentally sustainable in that it requires less energy compared to other means of transport like buses. The use of electricity as the chief source of power eliminates the use of fossil fuels which have contributed much to climate change. According to Cheshire (2010), maglev transportation systems use half the amount of energy used by a commercial aircraft while still carrying the same number of people. Vehicles and airplanes emit toxic fumes (carbon dioxide) into the atmosphere which has been attributed to contribute to global warming and air pollution. Use of electricity and magnetism does not produce of the by-products making the technology environmentally friendly and sustainable. Use of electricity and magnetism in transportation has the added advantage of reducing noise pollution, typical with the modern means of transport such as buses and airplanes. For instance, in maglev systems the trains do not have any moving parts and thus generate minimal noise.

Related Papers:  Conduction, Convection and Radiation

Use of electricity and magnetism will greatly reduce congestion on our roads. This will eliminate traffic jams on most cities. The use of maglev system enables mass transportation of people within a short time and using the least amount of energy. Using electricity and magnetism enables trains to achieve extremely fast speeds. This is made possible by the fact that there are no wheels or moving parts which may cause restrictions (Cheshire, 2010). In addition, maglev trains have a high reliability level, over 95 percent. This means that they are capable of delivering people to their desired destinations almost always on time. Although the initial costs involved in the development of rail tracks are high, the benefits are high and extend over a long duration. The system can last for a long period of time and requires little maintenance costs. This is because ware and tear is minimal as the train uses levitation while moving through the tracks, reducing friction (Cheshire, 2010).

Despite the high speeds achieved while using electricity and magnetism as a means of propulsion, the new transport system has a high safety record. Maglev trails are less likely to derail compared to other trains as they interlock with the tracks (Stewart, 2014). In addition, maglev trains are monitored using computers and thus reducing the chances of collision unlike in airplanes and cars.  Maglev trains ride on the magnetic waves generated by the alternating currents, which also makes it impossible for two trains on the same guide-way to collide (Stewart, 2014). The safety benefits offered by maglev transportation system will encourage governments to invest more in electricity and magnetism as a means of transport. In addition, more people will use maglev trains as their preferred mode of transport.


As maglev trains take root on major cities around the world, tech enthusiast envision a world where future cars will have the capability to achieve magnetic levitation on special guide-ways (Barry, 2009). In essence, the cars will be able to use electricity and magnetism as a means of propulsion from one point to another. Such cars may be equipped with a dual mode system which will allow them to move on normal roads and still use special guide-ways where magnetic levitation will be possible. This means that the vehicles will be able to use rubber tires in conventional roads and shift to a maglev system when need be. Cars using the maglev system will be safe, fast, less noisy, and fuel efficient just like trains that use the maglev system. In addition, such cars will be easier to maintain since there is reduced wear and tear in a maglev system. A number of concepts have been formulated which may eventually lead to development of new electric cars which may dwell on the principle of magnetic levitation. For instance, some researchers have suggested on the possibility adding electric motors to existing roads. This will enable normal cars as well as those using the maglev system to use the same roads (Barry, 2009).

Development of tracks for maglev trains

The development of tracks for maglev trains has minimal impact on land due to narrow nature of the guide-ways. Moreover, the elevated nature of the guide-ways ensures that there is minimal impact on the environment during construction (Stewart, 2014). For instance, a guide-way which passes through a national park will still allow animals to pass under with no obstruction. Construction of such guide-ways ensures that minimal damage occurs to the land. The guide-way can also be constructed over existing infrastructure such as roads or other railway lines.

In addition to magnetic levitation technologies, research in other efficient technologies is also taking root. Researchers are looking into developing superfast trains, known as hyperloop trains which can reach speeds of up to 800 mph (Gross, 2013). The hyperloop design uses the same technology as maglev trains, but travels in vacuum tubes hence eliminating friction. In maglev systems, the train encounters air friction which slows it down. However in a hyperloop system, trains will travel through vacuum tubes (Gross, 2013).

In conclusion, the challenges presented by use of fossil fuels such as high energy consumption, air pollution, road space, environmental pollution and global warming can only be overcome through innovation and disruption of the normal ways of doing things. The development of maglev trains holds great potential to creating an environmentally sustainable way of moving people and goods over long distances and in the shortest period using minimal energy. Use of electricity and magnetism in transportation will significantly reduce environmental pollution and increase safety. Use of electricity and magnetism has already been successfully applied in trains. Nonetheless, the technology is yet to be developed in vehicles and is only at the design levels.


Barry, K. (2009). Magnetic slot cars could solve our transportation woes. Retrieved from   

Brandon, J. (2013, Nov. 27). Five future transportation technologies that will actually happen.      FOX NEWS. Retrieved from        transportation-technologies-that-will-actually-happen/

Cheshire, G. (2010). Electricity and magnetism. London: Evans.

Gross, D. (2013, Aug. 13). Hyperloop vs. world’s fastest trains. CNN. Retrieved from   

Kirkland, K. (2007). Electricity and magnetism. New York, NY: Facts On File.

Stewart, J. (2014, Nov. 18). Maglevs: The floating future of trains? BBC. Retrieved from   

Conduction, Convection and Radiation

Conduction, Convection and Radiation






Conduction, Convection and Radiation

Heat is a form of thermal energy that can be transferred from one point to another. Heat transfer takes place through conduction, convection and radiation. Heat generally flows from a hot object to a colder one. This process continues until the two regions with temperature differences achieve a thermal equilibrium, and as long as the external source of heat is removed (Sundén, 2012). All metals are good conductors of heat. On the other hand, gases and non-metals fall into the category of poor heat conductors. These are also referred to as insulators. Heat conduction involves heat transfer within the object itself, while radiation may involve flow of heat between objects that are separated spatially. Heat transfer through convection occurs through a material carrier that facilitates flow of heat energy.  This paper will analyze in detail the above mentioned heat transfer mechanisms, giving relevant examples.


According to Baukal (2012), heat conduction is the flow of thermal energy between objects that are in direct contact, or heat transfer within the object itself. All matter is made up of particles or atoms. When particles get heated, they move randomly. In objects such as metal which are good conductors of heat, the heated particles move randomly causing the neighboring particles to move faster. As particles move within the object, they collide with each other in a haphazard manner. As the particles move in random manner, they transfer both potential and kinetic energy throughout the metallic object (Baukal, 2012). This energy is referred to as the internal energy.

The internal energy in objects is transferred by the action of randomly moving atoms as they interact with neighboring particles.  The heated atoms move and collide with the adjacent ones, and in the process transfer potential and kinetic energy to the adjacent atoms. As long as there is a source of heat, heat transfer from the hotter to the colder parts of the object continues. Electrons also flow within the object but in a back and forth manner. This prevents formation of electric current within the object. Conduction occurs in all states; in solids, liquids and gaseous substances. However, it is more pronounced in solids than in other forms due to the nature of the arrangement of particles in various states. In solids such as metals, atoms are packed closely together. This enables the vibrating atoms to transfer some of their energy to the neighboring atoms easily (S. Blundell and K. Blundell, 2006). In liquids and gases, the atoms are further apart, which means that there are fewer collisions between the heated and adjacent atoms.

Conduction is best explained through heating a metallic pan. When the pan is placed on fire, a person can comfortably touch the pan’s surface. As time goes by, the surface of the pan becomes hotter followed by the sides. Lastly, the handle also becomes hot. When the pan is heated, particles making up the base of the pan starts to move rapidly. These particles move and collide with neighboring particles causing them to move randomly. As the particles move, they transfer potential and kinetic energy obtained from the fire to the adjacent particles. The successive collision of particles within the pan causes temperatures to increase within the whole pan. This explains how the handle which is not in direct contact with the fire also becomes hot – conduction transfers heat throughout the pan. When one touches a cold object such as a metal rod it usually feels cold to touch. Heat is transferred from the body to the metal rod through conduction. This can explain why after holding the metal rod for sometimes it seizes to feel cold to touch.


According to Lienhard (IV) and Lienhard (V) (2008), convection is the transfer of heat through movement of liquids or gases from one point to another. Convection takes place in fluids and gaseous substances. In this method, heat transfer occurs through both fluid flow and diffusion. Convection mainly occurs through movement of fluid. Nonetheless, diffusion also causes molecular motion leading to heat transfer within fluids. When fluid or gas is heated, it becomes less dense. Thus, the warmer areas of the liquid which are in contact with the hot object rise to the cooler parts of the fluid. On the other hand, the cooler and dense part of the fluid moves to occupy the lower parts. This continuous cycle eventually results to the whole fluid obtaining even temperatures.

When fluids are heated, they expand just like solids. This is mainly due to the fact that heated particles move faster and randomly compared to cold particles within the fluid (Lienhard (IV) and Lienhard (V), 2008). As the particles move faster, the gaps between them increases and they take up more volume. However, the particles themselves do not change is size or shape. This leads to the hot parts having a lower density compared to colder parts of the fluid. This leads to the less dense part of the liquid rising and the colder parts of the fluid fall to warm regions. This process continues in what is known as the convectional currents. The process is maintained as long as there is a temperature gradient. When heating is removed, the convectional currents continue until a uniform density and temperature is obtained (Lienhard (IV) and Lienhard (V), 2008).

A good example of heat transfer via convection is heating of water using a stove. When boiling something such as elbow pasta, it is possible to observe the pasta rise from the bottom of the pan, move to the top and then sideways. Finally, the pasta sinks to the bottom of the pan and the cycle continues. When the water particles at the bottom of the pan become heated, they move faster and expand as well. This makes them less dense compared to the particles in the colder parts. This causes the less dense particles to rise, while the denser particles at the top fall to replace the rising water particles. Thus, movement of warmed water results to the whole water being heated up.

Convection is also observed in the heating of the atmosphere. The sun’s rays strike the earth and warm the earth’s surface. The air adjacent to the earth’s surface becomes warm and rises up, while the cold dense air falls to replace the rising warm air. Lastly, an electric heater placed in a room heats up the entire room through convection. The air close to the heater becomes warm and rises up, while the air at the top moves towards the heater. This results in the entire room becoming hot.


Radiation is transfer of heat through electromagnetic waves or photon emission. As such, heat radiation can occur without the need for intermediate matter unlike heat transfer through conduction and convection. This simply means that heat radiation can take place even in a vacuum. According to Sundén (2012), heat radiation occurs as part of electromagnetic spectrum found in energy emissions. Thus, heat radiation occurs as waves similar to sound waves or light waves. However, the range of waves differs in their frequency and wavelength. This is what distinguishes the various forms of waves. Heat radiation comprise of the infrared radiation in the electromagnetic spectrum. All objects with temperatures above absolute zero are capable of emitting electromagnetic waves. However, the amount of thermal radiation emitted depends with the temperatures of the object emitting thermal energy. Generally, hotter objects emit more of the thermal energy.

According to Sundén (2012), thermal radiation is generated when charged particles move about in matter. This occurs only when the temperature of the matter is above absolute zero, resulting to atomic collisions in particles within the matter. The atomic collisions lead to changes in the kinetic energy of the colliding particles. The resulting dipole oscillation produces electromagnetic radiation. In addition, a whole range of electromagnetic spectra is produced. It is important to note that transfer of heat through radiation does not depend on interaction of the matter.

The wavelength and frequency of the electromagnetic waves is determined by the temperature of the radiating object (S. Blundell and K. Blundell, 2006). The most common form of electromagnetic radiation comes from the sun in form of heat. The heat from the sun travels to Earth in form of electromagnetic waves. The waves travel through empty space, and millions of kilometers to reach Earth. Objects at room temperature also produce electromagnetic radiation, mainly as infrared rays. This form of radiation is invisible to the naked human eye. Nonetheless, it can be detected by using an infrared camera. Thus, even the human body produces thermal radiation which is invisible to the naked eye.

Read also: Use of Physics in Daily Activities

The coil of an electric cooker produces thermal radiation that is visible to the human eye. This occur when the coil is considerably hot and way above room temperatures. The glow on the coil which is thermal energy acts as a warning to users that the coil is hot. The incandescent light bulbs also produce thermal radiation that is visible to the human eye. This thermal energy also warms the bulb which is usually hot when one touches it.

In conclusion, heat is transferred through three methods; conduction, convection and through radiation. In conduction and convection, transfer of heat occurs through matter. Matter is made up of particles which vibrate and move randomly. In conduction, the particles move and vibrate vigorously, causing collisions with the neighboring particles and hence transfer of heat. Heat transfer occurs due to the disequilibrium that exists between temperatures of the object radiating heat and the surrounding objects. Heat transfer through convection occurs when warm fluid rises and is replaced by dense colder fluid. In radiation, heat transfer can occur through a vacuum. Heat transfer in radiation occurs in form of electromagnetic radiation.


Baukal, E. C. (2012). The John Zink Hamworthy Combustion Handbook, Second Edition. New    York, NY: CRC Press.

Blundell, S. & Blundell, K. (2006). Concepts in Modern Physics. Oxford: Oxford University        Press.

Lienhard, J. H. (IV)., & Lienhard, J. H. (V). (2008). A Heat Transfer Textbook. Cambridge,          Phlogiston Press.

Sundén, B. (2012). Introduction to heat transfer. Southampton: WIT Press.


Use of Physics in Daily Activities

Use of Physics in Daily Activities





Use of Physics in Daily Activities

Physics can generally be defined as a science that involves the study of forces and their interaction with the environment. Precisely, physics is the study of matter, energy, time and space, and how they interact with each other. Physics assumes the existence of four basic units which include: length, mass, electric current and time. These quantities are measured in terms of the metre, kilogram, second and Ampere respectively. According to physics, the four basic units are used to explain all other physical quantities.  Physics is used to explain how things move, and to analyze the forces that hold them together and/or forces that make them move. As such, it is hard to imagine modern life without application of physics in the daily activities. This paper will analyze the use of physics in daily activities, giving simple activities where physics is applied on a routine basis.


Physics is greatly used in communication. Communication may be carried out through a number of channels such as mobile phones, radio, television, internet and others. Electronic communication involves transmission of information from one person to another through cables or electromagnetic waves. A telecommunication system comprises of three basic elements: a transmitter, the transmission medium and the receiver. The transmitter receives information from the source and converts it to a signal. This signal is carried through a transmission medium to the receiver. The receiver decodes the signal to a form that the user can understand.

The communication channels used may either be physical or free space. Physical channels include the atmosphere, coaxial cables, and glass optical fibers among others. The free space includes channels such as radio waves, infrared waves, and ultraviolet light among others. Communication via these channels is made possible through application of physics. For example, radio stations rely on broadcasting of information from one source to multiple receivers through the use of radio waves. Mobile devices use electromagnetic waves to transmit information from one source to the receiver. Electromagnetic radiation comprises of magnetic fields and electric currents, with a give frequency. Electromagnetic radiation may occur naturally (radiation from the sun) or through man-made means. The application of physics in communication has enabled people to send and receive information easily in terms of time and cost.

Physics is applied in cooking

Modern cooking appliances such as the microwave, coils, inductive cooker and others rely on the principles of physics to perform their work. A microwave uses convection current to cook or warm food. Convection is defined as transfer of heat in liquid or gas from one region to another through circulation of currents. Air inside the oven is heated when electricity is switched on. Warm air rises to the top part of the oven and collects there. Since there is no cold air entering the oven, food placed at the centre of the oven is evenly cooked. Other forms of cooking such as use of coils also utilize laws of physics. When electric current passes through specially designed coils, heat is generated in the process turning the coil red. Heat is transferred from the coil through conduction. It is important to note that the energy used in cooking is also derived through the principles of physics. Electricity is generated using principles of physics. In addition, mining of oil, coal, gas and other energy resources rely on the same principles.

Regulating temperatures

Physics is applied in moderating room temperatures or in food preservation. Room temperature regulation is carried out by an air conditioner while food preservation is carried out by refrigerators. Temperature regulation is based on physic’s law on heat which explains that heat is absorbed when liquids change to gas through evaporation.  Air conditioners use this feature to cool indoor air. Air conditioners have special chemicals that evaporate and condense in specially designed coils. When the chemicals evaporate, they absorb heat making the air in the coils to become cold. Special fans draw warm air from the room over these coils leading to a chilling effect on the air passing above the coils and being released back into the room. This process repeats itself until the surrounding air becomes cooler. When the special chemical turns to gas, a reverse process is initiated turning it back to liquid state. This is achieved by compressing the gas at high pressure. Refrigerators use the same mechanisms and laws of physics in keeping the inside temperatures lower. The only difference is that refrigerators have an exterior housing that also acts as an insulator.

Physics makes work easier

At times, individuals are faced with the need to lift heavy objects that are beyond their strength. For example, one may need to lift a heavy load onto a lorry, or to lift a car so as to change a damaged tire. In order to succeed in doing so, one must apply one or more of the laws of physics. The individual lifting a heavy load onto the lorry may apply the laws of physics by using a lever or an inclined plane in order to reduce effort, and in so doing succeed in lifting the heavy load onto the lorry. Lifting heavy objects such as a car requires use of special equipments that works on the laws of physics. Jacks are often used to lift heavy objects. Jack uses force to lift objects, either generated by hydraulic press or turning a screw thread. The hydraulic cylinder uses pressure to generate force. It contains a small cylinder and a larger one. A force applied in one of the cylinders produces uniform pressure in both the cylinders. However, the resultant force on the larger cylinder is greater and hence gives a lift, making work easier.

Physicists have developed a wide range of tools that are used in making work easier. All these tools are based on laws on principles of physics. Apart from jacks, pulleys are also used to make work easier. Pulleys comprise of wheels which are connected in a manner to reduce work done in pulling loads. A pulley with two wheels is able to reduce the force needed to lift a load by half. Likewise, a pulley with four wheels reduces the force needed to lift a load by a scale of four. Thus, pulleys have a mechanical advantage. The mechanical advantage enables individuals lift heavier objects than they would under ordinary circumstances where principles of physics are not applied. All these use the principles of physics to make work easier.

Driving a car

Driving a car also requires the understanding of the basic principles of physics. This is regardless of whether the driver is aware of these laws or not. The driver must be aware of balance, and be able to keep the car in balance. Imbalance may be brought about by accelerating, decelerating or turning. To maintain the stability of the car, the driver must anticipate the action of the various forces on the car as it moves. Physics help engineers to determine the centre of gravity of various bodies. The centre of gravity helps engineers predict the likely results when a body is acted on by forces such as the gravitational force. Center of gravity also helps individuals to drive carefully especially when they put extra load on vehicles. When drivers put extra load on the roof of vehicles, they affect the centre of gravity and hence, they must be extra keen when taking turns or during acceleration and deceleration. A car is more likely to topple when taking a turn and while carrying a load on the roof.


When individuals decide to move over long distances, the preferred mode of transport is use of an aircraft. Aircrafts are designed using the laws of physics. Basically, aircrafts fly as a result of pressure differences that are caused by air flowing at different speeds. This can be explained by Bernoulli’s principle. Flying is thus wholly dependent on the principles of physics.

Diagnosis of various ailments

Physics is widely applied in the medical field to detect, cure and establish the cause of diseases. Medical imaging applies principles of physics to establish ailments in patients. Radiation oncology and nuclear medicine are commonly applied in cure of various ailments such as tumors and cancerous cells. Medical imaging involves testing, quality assurance and optimization. Common tests carried out on patients include X-rays, mammography, ultrasound and fluoroscopy. Such tests help reveal internal problems in the body of the patient. Nuclear medicine physics involves use of radiation to treat or identify diseases in patients. For example, radiation is used to kill malignant cells in patients suffering from cancer. All this involves application of the principles of physics that involve radiation and waves.

The importance of physics in people’s daily activities cannot be overlooked. Physics underlie the environment around human beings. Thus, for human beings to properly understand their environment, they must have a thorough knowledge on the basic principles of physics. In the complex environment, physics attempts to explain things and to predict what might happen if changes are introduced in such things. Physics is one of the disciplines that have contributed to a new and better understanding of the universe, and the consequent development of new products based on the principles of physics. As such, physics is often used in daily activities in the modern world. Physics is commonly used in communication, cooking, moderating temperatures, making work easier, driving, and in medicine among other uses.