LINEAR MOTIOIN

• Distance is the total length moved irrespective of direction.
• Displacement is the distance in a certain direction.
• Speed is the distance traveled per unit time irrespective of direction.
• Velocity is the rate of change of displacement.
• Acceleration is the rate of change of velocity.
• Displacement-Time Graph:
  • Gradient = Velocity
    

NON-LINEAR MOTIOIN

• Velocity-Time Graph:
  • Gradient = Acceleration
  • Area under graph = Change in displacement
    
  • Uniform acceleration and straight line motion equations:
    • v = u + at
    • s = ut + ¹/₂at²          s = vt – ¹/₂at²
    • s = ¹/₂(u + v)t           v² = u² + 2as

Determining Acceleration of Free Fall

• A steel ball is held on an electromagnet.
• When the electromagnet is switched off, the ball interrupts a beam of light and a timer is started.
• As the ball falls, it interrupts a second beam of light and the timer is stopped.
• The vertical distance h is plotted against t²
• s = ut + ¹/₂at²         and u = 0
• s = ¹/₂at²           h = ¹/₂at²
• Gradient = ^h/_t² = ¹/₂g
• Acceleration = 2 × g

Motion of Bodies Free Falling

Projectile Motion

• A projectile motion has a uniform velocity in one direction and a constant acceleration in the perpendicular direction.
  
• Horizontal motion = Constant velocity (speed at which the projectile is thrown)
• Vertical motion = Constant acceleration (Caused by the weight of the object, and constant free fall acceleration)
• Curved path – parabolic (y ∝ x²)
  
  

Motion of a Skydiver