Physics

A Hygrometer is an instrument used to measure the humidity of the air. A mechanical Hygrometer uses human or horse hairs which stretch as they absorb…

A Windsockis used at airports to indicate wind direction for takeoffs and landings. They help the pilots select the proper runway so that they can take…

This lecture introduce on Anemometer. An Anemometer measures wind speed. The cups catch the wind, turning a dial attached to the instrument. The dial shows the wind speed.…

A Psychrometer measures relative humidity. Two thermometers are used in a Psychrometer. A wet cloth covers the end of one of the thermometers. Water evaporates from…

Principle objective of this lecture is to present on Barometers. A Barometer measures air pressure. An Italian scientist named Torricelli built the first barometer in 1643. People still…

Major objective of this lecture is to present on Thermometers. A Thermometermeasures air temperature. A Thermometer works because matter expands when heated. Most thermometers are closed glass tubes…

Basic objective of this lecture is to present on How Do We Predict Weather. Since air masses interact in a relatively predictable way, meteorologists are able to…

General objective of this lecture is to present on Optical Illusions. An optical illusion is a visual stimuli that is perceived by the eyes and then comprehended…

Kirchhoff’s Laws of Spectral Line focus on: Light of all wavelengths shines on an atom. Only light of an energy equal to the difference between “floors” will…

Prime purpose of this lecture is to present on Sources of Infrared Light. Infrared light from the Sun accounts for 49% of the heating of Earth, with the rest…

A spectrum is the amount of light given off by an object at a range of wavelengths. A spectral line is a dark or bright line…

The normal human retina contains two kinds of light sensitive cells: the rod cells (active only in low light) and the cone cells (active in…