7. Free fall acceleration

Relative velocity and free fall acceleration

7. Free fall acceleration

• Freely falling motion of any body under the effect of gravity is an example of uniformly accelerated motion.
• Kinematic equation of motion under gravity can be obtained by replacing acceleration 'a' in equations of motion by acceleration due to gravity 'g'.
• Value of g is equal to 9.8 m.s^-2.
• Thus kinematic equations of motion under gravity are
  v = v₀ + gt                          (16a)
  x = v₀t + ½ ( gt² )          (16b)
  v² = (v₀)² + 2gx           (16c)
• The value of g is taken positive when the body falls vertically downwards and negative when the body is projected up against gravity.