1 One dimensional Motion Motion Along a Straight Line

2 Outline Introduction to Motion Position Distance and Displacement Speed and Velocity Acceleration Motion with constant acceleration Free-Fall Accerelation

3 Introduction to Motion Motion is a change of position of one body with respect to another body, frame of reference, or a coordinate system. Restriction of this lecture 1.The motion is along a straight line only 2.Forces that causes motion, will not be discussed. 3.The moving object is either a particle or particle -like

4 Intro. cont.... Classification of Motion 1.Kinematics kinematics does not takes into account the mass of an object and force (Consequently, NO momentum, Work or Power to be discussed. 1.KineticsDoes

5 Intro. cont.... Kinematics related Parameters Parameter Symbol Units Position or Displacement x m Speed or Velocity v m/s Acceleration a m/s 2 Time t s

6 Scalar and Vector quantities Time, Distance and speed are a scalar quantity. Displacement, velocity and acceleration are vector quantities Vector quantities have magnitude and direction, while scalar quantities only have magnitude.

7 Position Distance and Displacement Position is a quantity used to locate an object relative to some reference point, called origin Displacement is a change from one position to another position Ex.

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9 Position and Disp. cont.... Distance Displacement 1.the actual path between two points. the shortest path between two points 2.scalar vector

10 Example 100m 400m D CB A In the diagram above, there are two paths from A to D. The direct path is 400 m due East from A to D and is the displacement (and the distance) of AD. The other path, which goes from A to B to C to D, is 600 m and is the distance of that particular path. However, the displacement of the second path is still 400 m due East.

11 Speed and Velocity Notation is the i th position relative to the origin is a displacement, X 2 – X 1 Time interval, t 2 –t 1

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15 Instantaneous speed and velocity

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19 Acceleration Instantaneous acceleration

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21 Constant acceleration

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23 Equation of motion with Constant Acceleration v = v 0 + at x-x 0 = v t + ½ at 2 v 2 = v a(x – x) x – x 0 = ½ (v 0 + v)t

24 Free FAll

25 Example

26 Example

27 Example

28 References CD Physics version 2.0, Halliday, Resnick, Walker and Christman, John Wiley & Sons, Inc