Elec Class

learn electricity hands-on

0 1 / 20

Solved exercise · level 2 of 5

Voltage needed to recharge an accumulator

Skills: Calculate

Statement

An accumulator cell at the end of discharge has e = 1.2 V and r = 0.1 Ω. What voltage must be applied across it to recharge it with 8 A?

E′ = 1.2 V · r′ = 0.1 Ω · I = 8 A

Parametric exercise: the values change with every draw; these are one example.

Guided problem in 4 steps: unknown, formula, units, data, result.

1 hint from Bastaya available in the lab
Solution

Load: U′ = E′ + r′ · I = 1.2 + 0.1 × 8 = 2 V; check: I = (U′ − E′) / r′.

Other exercises of the chapter

Simulated time00:00:00
Q = I·t-
W = P·t-

Circuit diagram CEI 60617

How does it work?

Each big hole is a circuit node: you push one leg of a component into it. The 4 small holes around it are connected to it: chips and leads plug in there.

  1. Place a component Drag it from the palette: it snaps onto the grid. R rotates it.
  2. Bridge neighbouring holes Pick the jumper chip (or C) and drag on the board: bridged holes become a single node.
  3. Draw a lead For long links and the power supply: from one big hole to another, or to a terminal.
  4. Close the loop The circuit is solved live (Ohm, Kirchhoff) and the diagram follows.

Shortcuts

Del
delete
R
rotate
C
chip brush
Esc
cancel
wheel
zoom
0
fit the board
drag background
pan

Confirmer

Renommer

Importer un montage

Export