Magnetism, Magnetic Fields, and Electromagnetism
Magnetism and Magnetic Fields
Centuries before Christ, it was known that some iron ores, like magnetite, attracted small pieces of iron. This property is called magnetism. Objects possessing this property can be natural magnets, such as magnetite or the Earth itself, or artificial magnets made of magnetized iron or other ferromagnetic metals like manganese and cobalt.
Magnetic Field
A magnetic field is the disturbance caused by a magnet in an area of space. It manifests through interactions with other
Read MoreOptical Instruments and Human Vision
Optical Tools
Lenses and mirrors are used to build optical instruments. Some are well-known and commonly used: cameras, binoculars, or a magnifying glass. Others have great scientific interest, such as microscopes or telescopes. In both, the visual tool for our purpose, optical systems, is a friend because this is our natural optical system. Therefore, it is important to understand how our vision works.
Human Eye
The aim of objects and images of eyes is to be estigmatic without creating defects. Back-
Read MoreAstronomy Facts and Figures
1. The Electromagnetic Spectrum
The electromagnetic spectrum encompasses all electromagnetic radiation, including:
- Radio waves
- Microwaves
- Infrared
- Visible light
- Ultraviolet (UV)
- X-rays
- Gamma rays
2. Astronomical Unit
One astronomical unit (AU) is the average distance between Earth and the Sun, approximately 1.49 × 1011 meters.
3. Galaxies
A galaxy is a massive, gravitationally bound system of stars, gas clouds, planets, dust, dark matter, and possibly dark energy. Galaxies contain substructures like nebulae,
Read MoreVector Mechanics and Fundamental Physics Principles
Vector Characteristics
A vector is a physical quantity characterized by a point of application, a magnitude (or modulus), a direction, and a sense. Alternatively, it can be defined by a number of independent components. Vectors are essential to describe physical phenomena that cannot be characterized by a single value.
The four main characteristics of a vector are:
- Point of Application
- Magnitude (or Modulus): Determines the size of the vector.
- Direction: Defines the line in space along which the vector
A Summary of Scientific Theories and Concepts
Scientific Theories and Concepts: A Summary
What Does ‘Reduced to the Facts’ Mean?
Reduced to the facts means that some facts are inaccessible to experience because we cannot recreate certain events, such as the Big Bang. In such cases, we only have facts from which to draw hypotheses that cannot be empirically verified.
What is Epistemological Anarchism?
Epistemological anarchism suggests that scientific research should consider all factors, including myths and metaphysics, not just methodological
Read MoreElectricity: Direct Current, Alternating Current, and Generators
Direct Current (DC)
Direct current (DC) is the movement of electrons always in the same direction, from the point of highest potential (negative pole) to the point of lowest potential (positive pole).
Alternating Current (AC)
Alternating current (AC) is the movement of electrons along a conductor that changes direction at regular intervals.
Generators
Generators are devices that create electrical current by maintaining a potential difference between the ends of a conductor. They can be powered by various
Read More