MK

Physical Science-Chapter 11 

Kinematics

11A Describing Position

  • Wandering Planets
    • %%Mechanics%%: the study of motion
    • %%Kinematics%%: the study of how things move
    • %%Dynamics%%: the branch of physics that studies forces and how they can change an object’s motion
  • History of Mechanics
    • %%Retrograde Motion%%: the apparent motion of some planets in which they appear to slow down, stop, reverse their direction, and then resume their normal motion
    • %%Quantum Mechanics%%: the branch of physics that explores the behavior of matter and energy at the atomic and subatomic level
    • %%Relativistic Mechanics%%: the study of the motion of objects whose speeds are near the speed of light
  • Frame of Reference
    • %%Frame of reference%%: a coordinate system used to describe the motion of an object
  • Distance and Displacement
    • %%Distance%%: how far an object moves during a time interval
    • %%Displacement%%: a vector quantity that describes a change in position
  • Scalars and Vectors
    • %%Scalar%%: a measurable quantity that consists of magnitude (size) only
    • %%Vector%%: a measurable quantity with both magnitude and direction

11B Describing Motion

  • %%Speed%%: a scalar quantity indicating the rate at which an object moves

  • %%Velocity%%: a vector quantity indicating the rate at which an object’s position changes

  • Momentum

    • %%Momentum%%: a property of a moving system that is equal to its velocity times its mass
    • %%Conservation of Momentum%%: states that within a closed system - a system that is isolated from outside. pushes or pulls - the total momentum remains constant

11C Changing Motion

  • %%Acceleration%%: the rate of change in velocity

  • %%Free Fall%%: the motion of an object that falls due to gravity alone, with no other forces acting on it

  • Two-Dimensional Motion

    • %%Circular Motion%%: movement along a circular path
    • %%Centripetal Acceleration%%: acceleration that causes an object to move along along a circular path
    • %%Projectile Motion%%: the two-dimensional motion of any flying object whose path is determined by the influence of an external force only, such as gravity
    • %%Trajectory%%: the curved path of a projectile