Calcolatore Legge di Ohm

V = I × R. Tensione (V) = Corrente (I) × Resistenza (R). Potenza P = V × I = I²R = V²/R.

In serie le resistenze si sommano (R_tot = R1+R2+...), in parallelo si sommano i reciproci (1/R_tot = 1/R1+1/R2+...). Il parallelo è sempre minore della resistenza più piccola.

That voltage equals current times resistance. From any two of the three the third follows, and adding power, which is voltage times current, gives four quantities any two of which determine the rest.

In series the resistances simply add up, so the total is always larger than the biggest one. In parallel the reciprocals add, so the total is always smaller than the smallest resistor in the group.

Volts for voltage, amperes for current, ohms for resistance and watts for power. Milliamperes have to be converted first: 250 mA is 0.25 A, and entering 250 would give a result a thousand times too large.

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