The ultrasound waves fan out uni-directionally from the
MICE
|
COCKROACHES
REPELLER HOME, like fluorescent
light. Hard substances (walls, ceilings, furniture, glass, etc.)
promote better spreading out of the sound waves, as they
bounce off these surfaces, whereas soft materials (cardboard,
curtains,carpeting, etc.) absorb the sound waves.
Human
Bat
Mosquito
Butterfly
Fly
Cockroach
Cricket
Dog
Grasshopper
Rodent
Dolphin
Mole
Others
0.02
0.1
0.2
0.3
1
2
5
10
20
50
100
200
Khz
Audible Ultrasound
Table of
frequencies
within the
human hearing
range between
20 Hz y 20 Khz,
compared with
the approximate
hearing range of
different animals
and insects.
