Consider the circuit shown in (Figure 1). Suppose that ΔV = 7.5 V. What is the value of resistor R?
- billrussell42Lv 71 month agoFavorite Answer
total R = E/I = 7.5/0.1 = 75 Ω
R = 75 – 10 – 15 = 50 Ω
- husoskiLv 71 month ago
Ohm's law "E = IR" translates to:
7.5 = (0.100)(10 + 15 + R) . . . . in volt, amp, ohm units
75 = 25 + R
R = 50 (ohms)
The important step was to write I in ampere units instead of mA, to get units in a syste where there's no coefficient needed for Ohm's law. You could also use (mV, mA, ohms) or (volt, mA, K-ohms) as common choices.