Logiblocs Super Inventor's, Руководство изобретателя

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❷
DRAWER GUARD
You can fix up your special
drawer using some aluminium
foil as shown. If the drawer is
opened the aluminium foil will
brush past the two metal ends
of the Jack Plug wires so
completing the circuit and
setting the alarm off.
Hide the Logiblocs at the back
or beside the drawer where
there is usually a bit of space.
❸
METAL DETECTOR
Using the same Logibloc arrangement but without the
LONG DELAY, we can use the two metal ends of the
Jack Plug Wires to test for metal. Touch the ends of
the wires in two places on the item to be tested. If
the BLEEP sounds, then you have found metal
because metal conducts electricity
Remember not to put these wires anywhere near any
mains electrical outlets because that could be very
dangerous.
❹
WATER DETECTOR
Water also conducts electricity. You can test
for water by putting the two ends of the
Jack Plug wires into water. You may need
to add small plates of aluminium foil to the
ends to make the effect
greater.
Add the NOT between the IN and the
CROSS block and you could also tell when a
flow of water has stopped in a garden hose
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