Un ilusionista de 60 kg se deja caer desde la cima de una plataforma de 20 m de altura. Ignore la resistencia del aire. Determine la energía cinética en el punto 2 (cuando la altura es de 15 m).
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Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.