Work done

• Entry Level Certificate
• Learning objectives


  What work means in science<|>How energy transfers take place<|>When work is done<|>How to investigate friction<|>That work done against friction causes a temperature rise
• Work is done when a force makes an object move
• Work


  Measured in joules, J
• One joule is the work done when a 1 newton weight is raised by 1 metre
• Energy transferred


  Equal to the work done
• Friction


  Acts in the opposite direction to your pushing force
• As you do work against the frictional force, the bottom of the box gets hotter
• You need friction to be able to move or change direction
• Friction between the sole of your shoe and the ground

  Stops you from slipping or sliding
• Investigating friction


  1. Attach a block to a string

  2. Add a hanger to apply force

  3. Add weights until the block slides

  4. Record the weight added

  5. Change the surface and repeat
• Steps to investigate friction

  • Attach a block to a string
  • Add a hanger
  • Add weights
  • Record weight
  • Change surface
• Friction acts on the box because it is touching the floor
• Rubbing your hands together quickly makes them warm because you are doing work to overcome friction
• It is easier to push the box on a smoother surface
• To measure how much friction there is between two surfaces, you can follow specific steps
• Repeat the whole experiment to check the results are similar each time to make the experiment more reliable
• Energy store that has increased as the trolley moves up the hill

  Gravitational potential energy
• Factor that will affect how much work the student has to do

  Weight of the trolley<|>Steepness of the slope