Kinematics

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• Škola Gymnázium, Brno, Slovanské námestí 7
• Šablona III/2 Inovace a zkvalitnení výuky
  prostrednictvím ICT
• Název projektu Inovace výuky na GSN
  prostrednictvím ICT
• Císlo projektu CZ.1.07/1.5.00/34.0940
• Autor RNDr. Bc. Miroslav Hruška
• Tematická oblast Gravitational field and
  motion of bodies (gravitacní pole a pohyb teles)
• Název DUMu Kinetic energy of a rigid body
• Kód VY_32_INOVACE_FY.4.12
• Datum 2. 4. 2014
• Cílová skupina Žáci stredních škol s CLIL
  výukou fyziky v anglictine
• Klícová slova Kinetic energy, translational,
  rotational kinetic energy, moment of inertia
• Anotace Prezentace zavádí kinetickou energii
  rotujícího tuhého telesa a v této souvislosti
  moment setrvacnosti

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Gravitational field and motion of bodies

• 12. Kinetic energy of a rigid body

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Make pairs of words for bodies
solid torque line of action point of
action centre of gravity couple of
forces equilibrium rigid
tuhý pevný rovnováha moment síly vektorová prímka
pusobište dvojice sil težište
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Equilibrium complete the names

1. _ _ _ _ _ _
2. _ _ _ _ _ _ _ _
3. _ _ _ _ _ _

01
03 T
02
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Fill in the gaps

• Stability of a body (in a equilibrium)
  can be described by the amount of that
  must be done to move an object from the ..
  equilibrium into an equilibrium

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Fill in the gaps solution

• Stability of a rigid body (in a stable
  equilibrium) can be described by the minimum
  amount of work that must be done to move an
  object from the stable equilibrium into an
  unstable equilibrium

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Kinetic energy of a rigid body

• A body is composed of a huge number of particles
  (n)
• When the body is moving, each individual
  particle has its own kinetic energy
• Kinetic energy of the body is Ek Ek1 Ek2
  Ekn

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Translational kinetic energy

• If a rigid body is in translation, all particles
  (points) have equal velocities
• Thus

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Rotational kinetic energy

• If a rigid body is in rotation, all particles
  (points) have equal angular speeds
• Thus

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Moment of inertia

• Moment of inertia of a body, about a given axis,
  describes how the matter is distributed in the
  body with respect to the given axis
• Moment of inertia is a characteristic of the body
  and the given axis
• J kg.m2

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Moment of inertia

• Moment of inertia of a rod of length L and mass m
• Moment of inertia of a disk of radius R and mass m

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Explain

• Mass of a body gives us a measure of its
  resistance to translational acceleration
• Moment of inertia of a body gives us a measure of
  its resistance to rotational acceleration
• Kinetic energy of an object rolling down an
  inclined plane can be expressed as

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That is all for now

• Thank you for your attention

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• Materiál je urcen pro bezplatné používání pro
  potreby výuky a vzdelávání na všech typech škol a
  školských zarízeních. Jakékoliv další využití
  podléhá autorskému zákonu.
• Zdroje
• Bednarík, M., Široká, M. Fyzika pro gymnázia,
  Mechanika. Dotisk 3. vyd. Praha Prometheus,
  2004. 288 s. ISBN 80-7196-176-0
• Hornby, A. S. Oxford Advanced Learners
  Dictionary of Current English. 5. vyd. Oxford
  Oxford University Press, 1995. 1428 s. ISBN
  0-19-431423-5