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Wo audio speakers are placed on a vertical rail. speaker a is placed at head-level while speaker b is place at some variable height, \delta yδy, above speaker a. both speakers receive simultaneous input from a sine-wave generator so the speakers each produce a pure sinusoidal sound wave with a wavelength of 0.531 meters. calculate the lowest height that speaker b can be placed above speaker a to produce a minimum of sound heard by person standing \delta x = 7.86δx=7.86 meters directly in front of speaker a.

Clothes dryer uses about 7 amps of current from a 240 volt line. how much power does it use?

Una carga puntual de 3 x 10-6 c se coloca a 12 cm de una segunda carga puntual de - 1,5 x 10-6 c. calcular la magnitud fuerza eléctrica entre las cargas