Science 9 4th Quarter

• Projectile

  -          It is any object upon which the only force is gravity.

  -          It travels with a parabolic trajectory due to the influence of gravity.
• ·         There are no horizontal forces acting upon a projectile and thus no horizontal acceleration(0 m/s).
• ·         The horizontal velocity of a projectile is constant (a never-changing in value).
• ·         There is a vertical acceleration caused by gravity; its value is -9.8 m/s2
• ·         The vertical velocity of a projectile changes by 9.8 m/s each second.
• ·         The horizontal motion of a projectile is independent to its vertical motion.
• Projectile Motion

  -          It refers to the movement of an object through the air or space under the influence of gravity alone after being launched or thrown. This type of motions typically follows a curved path known as trajectory.

  -          The motion of a body projected horizontally at an angle other than 90° with the horizontal.

  -          It is the motion under the influence of gravity.
• 1.          Horizontal Component: ---

  -          This component of projectile motion describes the movement of the object in the horizontal direction.

  -          The horizontal motion of a projectile is characterized by a constant velocity, assuming no air resistance. This means that there is no acceleration acting horizontally on the projectile once it’s in the air.

  -          As a result, the horizontal velocity vx remains constant throughout the projectile’s flight.
• 2.          Vertical Component: I

  -          This component refers to the motion of the object in the vertical direction, influence by gravity.

  -          The vertical motion of a projectile is influenced by gravity, causing it to accelerate downwards.

  -          The vertical velocity vy decreases as the projectile rises, reaches a maximum height (0), and it increases as it falls back down.
• ·         Initial Velocity (Vo) – the speed and direction at which the object is launched.
• ·         Launch Angle (θ) – the angle at which the object is launched with respect to the horizontal.
• ·         Gravity (g) – the force that pulls the object downward, affecting its vertical motion. Its value is -9.8 m/s2.
• 1.          Trajectory – the curved path followed by the projectile as it moves through the air or space.
• 2.          Range – the horizontal distance travelled by the projectile from the launch point to the point where it hits the ground or another surface.
• Different Terms

  ·         Vo = Initial Speed

  ·         Vox = Horizontal Speed/Velocity

  ·         Voy = Vertical Speed/Velocity

  ·         dx = Horizontal Distance/Displacement

  ·         dy = Vertical Distance/Displacement or Height

  ·         g = Gravity

  ·         t = time