Data Sheet

-33-
41. LED Colors
Build the circuit, turn the hand crank
generator (94 & 99) and you will light up the
heart LED (69) and the star LED (70) at the
same time. If you turn the hand crank (94)
faster, you will see the lamp (76) will light and
be brighter the faster you turn.
42. Hand Crank Generator-
controlled Three LEDs in
Parallel
Build the circuit, turn the hand crank
generator (94 & 99) and you will light up
three LEDs at the same time. If you turn
the hand crank generator (94 & 99) in the
opposite direction, you will only light up the
bi-directional LED (71).
LEDs produce different colors by transmitting
light waves with different wavelengths. Light
waves cycle up and down and a wavelength
is the distance between successive crests
of the wave. Red light has a wavelength of
around 665 nanometers, while blue light has
a wavelength of around 470 nanometers.
1st level
1st level