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8. Pressure of solids, liquids and gases
The Pyramid of the Sun was built in
the 2nd century ce and later used by
the Aztecs in what is now Mexico.
The Triumph of Astana skyscraper
textbooks nis edu kz
was built in 2006. From what you can
see, what do these buildings have in
common? In your opinion, why are
many tall buildings built in the same
way, even nowadays?
Pyramid of the Sun,
Teotihuacan, Mexico
Triumph of Astana skyscraper
In Unit 6 and Unit 7 you learnt:
✔ what the density of an object is
✔ how to calculate the density of objects for Physics
regular and irregular shapes
✔ about different types of force
In this unit you will learn:
✔ what pressure is and what pressure
depends on
✔ why liquids and gases exert pressure
✔ how pressure in liquids and gases differs
from pressure in solids
✔ what upthrust force depends on and why
it occurs
✔ about the conditions required for buoyancy
Key phrases:
✔ Pressure in liquids and gases depends on …
✔ Pressure in solids increases/reduces if …
✔ Upthrust/Archimedes force acts on an object …
and is directed …
✔ An object floats if … ; sinks if … ; and floats up
if …
CCL In Chemistry classes you learnt that an
object consists of particles, and in Physics
classes you will understand that pressure
created by gases is connected with the motion
of these particles. In Geography classes you
learnt about atmospheric pressure and that
it is measured with a barometer. Studying
Physics you will find out about devices you
can use to measure pressure greater or
less than atmospheric pressure. In Maths
classes you learnt how to draw parallel and
perpendicular lines on a plane. These skills will
help you to solve problems when calculating lift
and upthrust.
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