Page 143 - How It Works - Book Of Amazing Answers To Curious Questions, Volume 05-15

Transport

How do emergency

vehicle lights work?

ixed to the top of police, fi re a see-through unit with a single
Fand ambulance service light bulb inside has long been a
vehicles, flashing blue lights are trusted ally of the emergency

deployed in the event of an services – and its magic is in the
emergency. Their bright fl ashes illusion it creates.
grab the attention of other road Of course, bulbs can’t keep

users from a distance, allowing flashing on and off for long periods
them to take evasive steps in good or they’ll blow, so the illusion is
time to make sure the emergency created by a rotating base with a
vehicle can pass through safely vertical refl ector affixed to it,

and quickly, even in heavy traffi c, moving around a fixed light bulb.

which is crucial when responding The reflector redirects light
to an emergency call. outward from one side, while
Although brighter, more effi cient blocking the light out to the other.
blue LED lights are now When the base is rotated fast, this
© Thinkstock commonplace on modern police creates the ‘on-off’ illusion of a
flashing blue light atop an
cars, ambulances and fi re engines,

the old-fashioned method of using emergency vehicle.
Why do returning space ships land in the sea?

ot all returning spacecraft land in the program. Because it launches from Cape would freeze any exiting cosmonauts, while
Nsea. The Russian Federal Space Kennedy (formerly Cape Canaveral) in landing in international waters could be
Agency’s Soyuz craft – which transports Florida, there was plenty of surrounding politically tricky. However, there is plenty of

astronauts and cosmonauts to the water that’s safe and available for astronauts sparsely populated, flat land in Russia.
International Space Station – lands on the to land in and open their capsule. The Recovering astronauts from the sea

flat steppes of Kazakhstan. In fact, Russian Russian program launches from the Baikonur ultimately presented NASA with many
space programs have always used ground- Cosmodrome, located in the land-locked challenges, and that’s part of why the design
based landings, while NASA used country of Kazakhstan. Due to this location, for the Space Shuttle program incorporated
splashdowns until the Space Shuttle a splashdown in the closest Russian waters landing on a runway.

How It Works 143