Shaking in
space?
Plate compactors are even used for physical
training by astronauts in space! This kind of
training will become even more important in
the future, as
astronauts
take longer and
longer trips into space. A trip to Mars and
back can last more than 2 years. During that
time, the astronauts will be subjected to zero
gravity and their muscles won’t be bearing
any weight. That means that their muscles
will atrophy, or break down, without
training.
WONDERFULLY DIZZY…
Have you ever watched a figure skater sp
in in place? This
“figure” is called a pirouette. Often, an ar
m or leg is
extended out at the start of the spin, and t
hen pulled in tight
to the body. That makes the mass shift c
loser to the axis of
rotation, which runs vertically through t
he middle of the
figure skater’s body.
In terms of physics, you would say that t
he body is no
longer so “inert.” That makes the speed of rot
ation increase
and the figure skater spin faster and fast
er.
WHY DO YOU GLIDE ON ICE?
When you go ice skating, you move the skates’
blades across the ice. The friction creates
heat. The ice beneath the blades melts and
forms a thin film of water. Due to the film of
water, the friction between blade and ice is
very low, so you can glide along effortlessly,
as if you were light as a feather.
CHECK IT OUT
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