Measure emf of voltaic cell
consisting of zinc and copper strips inserted in a lemon. Measure
current to
show that the internal resistance is large. Lemon battery can be
used
to power a buzzer.
NOTES
Use Radio Shack buzzer #
273-065.
Buzzer will sound with as little as 0.5 V, 0.03 mA.
Lemon: V =
~0.9 V, I = ~0.5 mA. Maximize current by rolling/pressing lemon
on
table, putting metal strips in deep and close together.
