Elec Class
learn electricity hands-on
Solved exercise · level 2 of 5
Skills: Build, Calculate
We want 20 C to flow in 20 s in this circuit. Set rheostat P1 (slider) to get the required current (within 5 %), read on A1.
Parametric exercise: the values change with every draw; these are one example.
I = Q / t = 20 / 20 = 1 A. At 12 V, the rheostat must present R = U / I = 12 / 1 = 12 Ω.