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Sound
No – dogs can hear higher notes than people, and squid can’t hear at all.
Speeding sound
All sounds travel at the
same speed, but they
travel more quickly
through solids and
liquids than through
gases. Supersonic jets fly
faster than the speed of
sound, so they can pass
over you before you hear
their sound.
The echo effect
Some animals use sound to communicate or
to hunt. Dolphins “talk” by making clicks,
barks and other sounds that other dolphins
recognize. They also use clicks to find
food – the sound bounces
back off objects as an
echo, so the dolphin
can establish their
shape and position.
This is called
echolocation.
When sounds bounce
back, the dolphin
can tell if the object
is a yummy fish or
another dolphin!
When a supersonic jet breaks the speed
of sound, it catches up with the sound
waves in front of it and squashes them.
As the air is squashed, it produces a
sound called a “sonic boom”.
