Step 5: Step 5: Test speaker (Battery test)
Using the 1.5-V battery with the loudspeaker, briefly connect the ends of the coil wires to the battery terminals. (One student lightly taps one battery connection on and off while her partner lightly touches the top of the lid or listens to the speaker close to her ear.) Students
feel and hear a light tapping as the battery connection is alternately made and broken. They might also be able to see the lid moving.