What is Projectile Motion?

Instructional Objectives: Students will be able to: –Define Projectile Motion –Distinguish between the different types of projectile motion –Apply the concept to a toy car and measure its velocity

Projectile Motion Two-dimensional motion of an object –V–Vertical –H–Horizontal

Types of Projectile Motion Horizontal –Motion of a ball rolling freely along a level surface –Horizontal velocity is ALWAYS constant Vertical –Motion of a freely falling object –Force due to gravity –Vertical component of velocity changes with time Parabolic –Path traced by an object accelerating only in the vertical direction while moving at constant horizontal velocity

Examples of Projectile Motion Launching a Cannon ball

Equations X- Component Y- Component Vectors Note: g= 9.8 m/s^2

Factors Affecting Projectile Motion What two factors would affect projectile motion? –Angle –Initial velocity Initial Velocity Angle

Part 1. Motion of Objects Projected Horizontally

v0v0 x y

x y

x y

x y

x y

x y Motion is accelerated Acceleration is constant, and downward a = g = -9.81m/s 2 The horizontal (x) component of velocity is constant The horizontal and vertical motions are independent of each other, but they have a common time g = -9.81m/s 2

ANALYSIS OF MOTION ASSUMPTIONS: x-direction (horizontal): uniform motion y-direction (vertical): accelerated motion no air resistance QUESTIONS: What is the trajectory? What is the total time of the motion? What is the horizontal range? What is the final velocity?

Part 2. Motion of objects projected at an angle

x y Motion is accelerated Acceleration is constant, and downward a = g = -9.81m/s 2 The horizontal (x) component of velocity is constant The horizontal and vertical motions are independent of each other, but they have a common time a = g = m/s 2

PROJECTILE MOTION - SUMMARY  Projectile motion is motion with a constant horizontal velocity combined with a constant vertical acceleration  The projectile moves along a parabola