Electrical4U What is a Darlington Transistor? A Darlington transistor (also known as a Darlington pair) is an electronics component made via the combination of two BJTs (Bipolar Junction Transistor) connected in such a way that it allows a very high amount of current gain. This is achieved through a compounding amplification, whereby the current is amplified … Read more
What are the Fresnel Equations? The Fresnel Equations (also known as Fresnel coefficients) are defined as the ratios of the electric field of reflected and transmitted waves to the incident wave. These complex ratios describe both the relative amplitude and the phase shifts between the waves. The Fresnel Equations describe the reflection and transmission of … Read more
What is an Arduino? Arduino is an open-source hardware development board. It has a programmable circuit board and a software (IDE- Integrated Development Environment) that runs on Mac, Windows, and Linux. Arduino was developed at the Ivrea Interaction Design Institute by Massimo Benzi in Italy. It was developed for fast prototyping, and aimed at people … Read more
What is Radiometry? Radiometry is a technique to measure electromagnetic radiation for any wavelength. Photometry is similar to radiometry, but photometry is related to visible light signals only, while radiometry includes signals of any wavelength – like ultraviolet, infrared, and visible light. Radiometry detects radiation from materials and substances. According to Planck’s law, all materials … Read more
What is a Rogowski Coil? A Rogowski coil is defined as an electrical device used to measure alternating current (AC), including high-speed transient, pulsed, or sinusoidal currents. It is named after the German physicist Walter Rogowski. A Rogowski coil is an evenly wounded coil with N number of turn and constant cross-section area A. There … Read more
What is a Slip Ring? A slip ring is defined as an electromechanical device that is used to connect a stationary system to a rotating system. It is used in applications that require rotation while transmitting power or electrical signals. The slip ring also is known as an electrical rotary joint, rotating electrical connector, or … Read more
Physics is the natural science that seeks to understand the fundamental principles governing the universe. From the subatomic particles to the vast expanses of space, physics covers a broad spectrum of phenomena. It’s a field that has given rise to revolutionary concepts like quantum mechanics, relativity, and the theory of everything, shaping our understanding of … Read more
What is DC Current? DC stands for Direct Current, although it is often called “DC Current”. DC current is defined as a unidirectional flow of electric charge. In DC current, the electrons move from an area of negative charge to an area of positive charge without changing direction. This is unlike alternating current (AC) circuits, … Read more
What is Reactance? Reactance (also known as electrical reactance) is defined as the opposition to the flow of current from a circuit element due to its inductance and capacitance. Greater reactance leads to smaller currents for the same applied voltage. Reactance is similar to electric resistance, although it differs in several respects. When alternating current … Read more
What is Reflectance Reflectance is defined as the ratio of the radiant flux reflected from the surface or body of a material (фr) to the incident radiant flux (фi). Reflectance is denoted by ρ (or p). \[ \rho = \frac{\phi_r}{\phi_i} \] The reflectance is a ratio of radiant flux. Therefore, it is unitless. The reflectance … Read more