Frictional Forces

• define drag


  the force that opposes a body's motion through a fluid
• list 5 factors that affect drag

  • velocity
  • cross-sectional area
  • shape and aerodynamics
  • texture
  • properties of the fluid (eg. density)
• what is the relationship between drag and velocity?

  drag is directly proportional to velocity^2
• what is the equation for acceleration when a body is released from rest and falls due to gravity?


  a=g
• what is the equation for acceleration when a body dropped from rest is accelerating?

  a=(mg-drag)/m
• what is the acceleration of an object travelling at terminal velocity?

  0ms^-2