Solar Radiation: Types and Atmospheric Absorption
Solar Radiation
Solar radiation is the main source of energy received by the atmosphere. The radiation from other celestial bodies is very small. Light and heat are forms of energy transmitted by electromagnetic waves that propagate through space. The length of these waves is so small they are measured in microns. Of all the radiation from the sun, only the part called the visible range is perceived by the human eye. Electromagnetic energy is transmitted in wave form, and radiation is precisely the
Read MoreGeometrical Optics and Vision Correction: Understanding Light and Eyesight
Geometrical Optics: Principles and Applications
Geometrical optics deals with the phenomena of light rays, including reflection, refraction, and analysis of their deviations. It is based on these assumptions: light travels in a straight line in a homogeneous and isotropic medium, and the reflection and refraction of light rays are reversible and comply with Snell’s law.
Diopters and Optical Systems
A diopter is the surface of an optical system separating two different environments with varying refractive
Read MoreA Brief History of Physics and Measurement
History of Physics
Physics is the natural science that studies matter, its motion and behavior through space and time, and the related entities of energy and force.
Key Figures in Physics History
- Aristotle (384-322 BC) tried to establish general principles that ruled the behavior of natural bodies, both living and inanimate, also celestial and terrestrial bodies, applying concepts like motion, change of place, and change of size or number.
- Archimedes (287-212 BC) is considered one of the greatest mathematicians
Key Concepts in Modern Physics: A Concise Review
Key Concepts in Modern Physics
This document outlines fundamental concepts in modern physics.
1. Black Body Radiation
A black body is an ideal object that absorbs all electromagnetic radiation that reaches it. T is the body’s temperature, and k is the electromagnetic energy emitted due to that temperature. The wavelength of black body radiation follows two laws:
- Wien’s Law: Intensity decreases with increasing temperature.
- Stefan-Boltzmann Law: The intensity of radiation emitted by a black body is proportional
Quantum Physics: Key Concepts and Phenomena
Quantum Physics
1. Thermal Radiation and Black-body Radiation
The electromagnetic energy emitted by a body due to its temperature is called thermal radiation. Thermal radiation varies with temperature and the composition of the body. Bodies whose thermal radiation depends *only* on temperature are said to exhibit black-body radiation and have the following characteristics:
- The total power (P) emitted by a surface at temperature (T) satisfies the Stefan-Boltzmann Law: (where σ = 5.67 x 10-8 W/m2K4)
Friction, Photosynthesis, Matter, and Scientist
Friction
Newton’s Laws:
- 1st: An object remains at rest, or in motion at a constant speed in a straight line, unless acted upon by an external force.
- 2nd: Force = Mass * Acceleration
- 3rd: For every action, there is an equal and opposite reaction.
Velocity: Velocity is the speed in combination with the direction of motion of an object.
Positive Acceleration: Positive acceleration occurs when an object is speeding up in the positive direction. For example, if a car is moving forward and its velocity is increasing,
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