Search results
Results from the WOW.Com Content Network
The problem with matrix circuits is that, when several notes are pressed at once, the current can flow backward through the circuit and trigger "phantom keys" that cause "ghost" notes to play. To avoid triggering unwanted notes, most keyboard matrix circuits have diodes soldered with the switch under each key of the musical keyboard .
The first mention of radar in the UK was a 1930 suggestion made by W. A. S. Butement and P. E. Pollard of the Army War Office's Signals Experimental Establishment (SEE). [1] [2] They proposed building a radar system for detecting ships to be used with shore batteries, and went so far as to build a low-power breadboard prototype using pulses at 50 cm wavelength (600 MHz).
A dipole is characterised by its dipole moment, a vector quantity shown in the figure as the blue arrow labeled M. It is the relationship between the electric field and the dipole moment that gives rise to the behaviour of the dielectric. (Note that the dipole moment points in the same direction as the electric field in the figure.
The monopole antenna is essentially one half of the half-wave dipole, a single 1 / 4 wavelength element with the other side connected to ground or an equivalent ground plane (or counterpoise). Monopoles, which are one-half the size of a dipole, are common for long-wavelength radio signals where a dipole would be impractically large.
A succession of sparks jumping from the key to the back of his hand showed that lightning was indeed electrical in nature. [16] He also explained the apparently paradoxical behavior [17] of the Leyden jar as a device for storing large amounts of electrical charge in terms of electricity consisting of both positive and negative charges. [14]
Electrical Engineering: Problems and Solutions. Dearborn Trade Publishing. ISBN 978-1-4195-2131-7. Karalis, Edward (18 September 2003). 350 Solved Electrical Engineering Problems. Dearborn Trade Publishing. ISBN 978-0-7931-8511-5. Krawczyk, Andrzej; Wiak, S. (1 January 2002). Electromagnetic Fields in Electrical Engineering. IOS Press.
Electrical conductivity (or specific conductance) is the reciprocal of electrical resistivity. It represents a material's ability to conduct electric current. It is commonly signified by the Greek letter σ , but κ (especially in electrical engineering) [citation needed] and γ [citation needed] are sometimes
Inductance is the tendency of an electrical conductor to oppose a change in the electric current flowing through it. The electric current produces a magnetic field around the conductor. The magnetic field strength depends on the magnitude of the electric current, and therefore follows any changes in the magnitude of the current.