Elec Class

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Solved exercise · level 2 of 5

Cell autonomy

Skills: Calculate

Statement

A roadworks warning light draws an average current of 0.5 A. It is powered by a cell of usable capacity 4.5 Ah. For how long (in hours) does it run without interruption?

Q = 4.5 Ah · I = 0.5 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

t = Q / I = 4.5 / 0.5 = 9 h.

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

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