Is your backpack heavy? Have you ever tried to find ways to help you move it around more easily? Force is a measure of how hard you have to work to move something. In this activity, you will compare the force needed to lift your backpack straight off the ground to the force needed to pull the backpack up a ramp.


  • Lift your backpack to a chair in two different ways.
  • Measure the force needed for each way of lifting.
  • Make observations.
  • Think of ways ramps are used to help people move things more easily.