Qasim Tariq 11-01-2020Notes

After studying this unit, the students will be able to:

  • define like and unlike parallel forces.
  • state head to tail rule of vector addition of forces/vectors.
  • describe how a force is resolved into its perpendicular components.
  • determine the magnitude and direction of a force from its perpendicular components.
  • define moment of force or torque as moment = force x perpendicular distance from pivot to the line of action of force.
  • explain the turning effect of force by relating it to everyday life.
  • state the principle of moments.
  • define the centre of mass and centre of gravity of a body.
  • define couple as a pair of forces tending to produce rotation.
  • prove that the couple has the same moments about all points.
  • define equilibrium and classify its types by quoting examples from everyday life.
  • state the two conditions for equilibrium of a body.
  • solve problems on simple balanced systems when bodies are supported by one pivot only.
  • describe the states of equilibrium and classify them with common examples.
  • explain effect of the position of the centre of mass on the stability of simple objects.

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  • 9th Physics Notes
  • 9th Physics Chapter 4
  • Matric Notes
  • Class IX Helping Notes
  • Matriculation Notes
  • Matric Part-1 Notes

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