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LET’S GET DETECTING
❶
HUNT THE SPY!
Plug the Logiblocs together as for the Logi Guard on page 12 and record a
message in the usual way – “I’m here!”. Replace the BUTTON with the
LIGHT SWITCH. Hide the Logiblocs behind things in a dark room. Do not
cover the lens of the LIGHT SWITCH and make sure that the flashlight will
trigger the Logiblocs when it is shone directly at the hidden LIGHT SWITCH.
Take it in turns to hide the Logiblocs in ever more clever places.
❷
CHECK FOR METAL!
We can use the two metal ends of the Jack
Plug Wires to test for metal. Metal
conducts electricity and so you can test all
sorts of objects. Use the same Logibloc
arrangement that you used on page 14.
Test a pencil. Does the lead inside conduct
electricity? So it’s not just metal that
conducts electricity. Your message should
be “Look! I conduct electricity!”
Remember not to put these wires
anywhere near any mains electrical outlets
because that could be very dangerous.
❸
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.
Your message could be “Look! I’m wet!”
Add the NOT between the IN and the
RECORDER blocs and you could also tell
when a flow of water has stopped in a
garden hose
