Elec Class
learn electricity hands-on
Solved exercise · level 3 of 5
Skills: Calculate
What current would an ammeter of internal resistance 0.1 Ω carry if placed straight across an accumulator cell of e = 1.5 V and r = 0.1 Ω?
Parametric exercise: the values change with every draw; these are one example.
Only r and the ammeter resistance limit the current: I = e / (r + Ra) = 1.5 / (0.1 + 0.1) = 7.5 A, almost a short circuit.