Instructions

Actually, there are three brightness levels. Switch 1 is for sim-

ple brightness and switch 2 for tenfold brightness. But if both

switches are on, the result is eleven times the brightness. You

can easily test it: Turn on switch 2 and turn switch 1 on and

off alternately. The difference is, however, very insigniﬁcant

and hardly recognisable.

Voltage, resistance and current

As is known, the electrical voltage is measured in volts (V). The

battery is 9 V. And a resistance is measured in ohms (Ω) or

kilo ohms (k Ω = 1,000 Ω). But there is another very important

measure: the electrical current, which is measured in amperes

(A) or at low currents in milliamps (mA = 1/1000 A).