Qasim Tariq 11-01-2020Notes

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

  • define momentum, force, inertia, friction and centripetal force.
  • solve problems using the equation Force = change in momentum / change in time.
  • explain the concept of force by practical examples of daily life.
  • state Newton's laws of motion. distinguish between mass and weight and solve problems using F= ma, and w = mg.
  • calculate tension and acceleration in a string during motion of bodies connected by the string and passing over frictionless pulley using second law of motion.
  • state the law of conversation of momentum.
  • use the principle of conservation of momentum in the collision of two objects.
  • determine the velocity after collision of two objects using the law of conservation of momentum.
  • explain the effect of friction on the motion of a vehicle in the context of tyre surface, road conditions including skidding, braking force.
  • demonstrate that rolling friction is much lesser than sliding friction.
  • list various methods to reduce friction.
  • explain that motion in a curved path is due to a perpendicular force on a body that changes direction of motion but not speed.
  • calculate centripetal force on a body moving in a 2circle using mv /r.
  • state what will happen to you while you are sitting inside a bus when the bus
    (i) starts moving suddenly
    (ii) stops moving suddenly
    (iii) turns a corner to the left suddenly
  • write a story about what may happen to you when you dream that all frictions suddenly disappeared. Why did your dream turn into a nightmare?

Post Tags:

  • 9th Physics Notes
  • 9th Physics Chapter 3
  • Matric Notes
  • Class IX Helping Notes
  • Matriculation Notes
  • Matric Part-1 Notes

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