Electromagnetic waves are electric and magnetic fields traveling through free space at the speed of light; in other words, an electromagnetic wave is a propagating electromagnetic field that travels with finite velocity as a disturbance through a medium. The field … Read More
Category: Classical Physics
Articles on classical mechanics, optics, thermodynamics and electromagnetism.
Lightning as an Electrical Phenomenon
Friction produces electric charges high in the atmosphere. This occurs when small particles such as water droplets and ice collide or rub against one another. Wind, among other factors, separates these charges and large electric forces develop between the ground … Read More
The Principle & Application of Nuclear Magnetic Resonance (NMR)
Nuclear magnetic moments (along with electronic magnetic moments) precess (spin) when placed in an external magnetic field, B. The frequency at which they precess, called the Lamor precessional frequency, wL, is directly proportional to the magnetic field.… Read More
The Physics Behind Magnetic Resonance Imaging (MRI)
MRI provides physicians with a tool to assess a patient’s health. To have an MRI exam, the patient lies in a very strong magnetic field that is generated by powerful magnets. The MRI machine then applies radio waves to the … Read More
The Operation of Magnetically Levitated Trains (Maglevs)
Magnetic levitation (maglev), take place when the magnetic interaction is strong enough to balance the force of gravity. The like poles of two magnets repel one another, and if the magnets are placed vertically and the strength of the repulsion … Read More
Newton’s Law of Universal Gravitation
Newton’s law of universal gravitation is a physical law that states that every particle attracts every other particle in the universe with the force of attraction directly proportional to the product of the masses and inversely proportional to the square … Read More
Basic Facts about Superconductors
Most of the conductors we use in our daily life are metals such copper wire. While these conductors are useful in many applications, they are not perfect as they have at least a small amount of resistance, which implies that … Read More
Coulomb’s Law and Electric Field
According to Benjamin Franklin, we have two types of electric charges i.e. positive and negative charges. Positive and negative charges attract, but positive charges repel each other, as do negative charges.
The force F that a pair of electric charges … Read More
Uses of Static Electricity
Even though static electricity can be unsafe, it has some uses as discussed below:
- In vehicles spark plugs ignite fuel injected into the engine’s cylinders.
- Copier machines use static electricity. To produce a copy, most modern copier machines make a
Newton’s Laws of Motions
Before Einstein, physicists believed that the behaviour of almost everything was controlled by three rules called “Newton’s Laws of Motion”. The basic point was to relate the motion of objects to the “forces” that act on that object. These forces … Read More