Page 60 - How It Works - Book Of Amazing Answers To Curious Questions, Volume 05-15

Why does my

voice sound

different on

a recording?

recording only captures part of the
A sound of your voice – the part that
travels through the air to the microphone.
This is the same as the sound that reaches
the ears of everyone else, so the recording
sounds just like your real voice to them. But
when we normally hear our own voices, the
sound is a combination of this airborne
sound, and the sound that travels through
the bones of our jaw and skull. This favours
the lower sound frequencies, so we all hear
our voices as deeper and
more resonant that Why are mice typically used
the rest of the
world does.
for animal testing in labs?

ice are convenient because they are diseases or quickly stimulate the growth of
Msmall, easy to keep and quick to cancer tumours. Testing medical
breed. They are mammals like us and have treatments on mice is generally considered
99 per cent of the same genes as us. Mice more ethical than using highly
have been used for long enough now that experimental drugs on humans, but it is

there are lots of mutant varieties only a first step. Many drugs that cure
How do commercially available to researchers that cancer in mice have turned out to be less
allow them to simulate various human
effective in humans.
insecticides Testing medical treatments on mice is
kill creepy generally considered more ethical than using

crawlies? highly experimental drugs on humans

here are many types of
Tinsecticides and each works in a
different way. Old-fashioned
insecticides, like organophosphates What causes lens
and DDT, attack the nervous system.
They are effective but they don’t just
work on insects and can cause serious flare in photos?
harm to humans. Newer insecticides

are made to specifi cally target ens flare can be problematic as it’s capable of
unwanted species. The insecticides L drastically reducing contrast in an image as well
used to kill fleas on your dog stop the as introducing halos and scattered polygonal shapes

insects from producing a new across the frame. That being said, many

exoskeleton, preventing them from photographers opt to include lens flare in their
shedding their skin. Other insecticides photos for artistic effect. It occurs when a bright
used to kill beetle and moth light, such as from the Sun, hits the surface of the
infestations, contain chemicals that lens at an unusual angle, as opposed to straight on.
mimic insect growth hormones, This strong stream of light will then refl ect and
keeping the insects in a juvenile state bounce off multiple elements within the lens before

to stop them reproducing. finally reaching the sensor where it will be recorded
as part of the picture.

60 How It Works