Work done and energy transfer

• Work done


  Energy transferred when a force is used to move an object
• Calculating work done


  Force in Newtons x Distance in meters
• The distance must be in the line of action of the force
• 1 Newton meter of work = 1 Joule
• Work done calculation


  • Force of 20 N x Distance of 2 m = 40 J
• Kinetic energy


  • Stored in a moving object
• Brakes are applied to a moving car

  Kinetic energy is transferred to thermal energy in the brakes
• Work done calculation during braking

  • Force of 3000 N x Distance of 15 m = 45,000 J
• Gravitational potential energy


  • Stored when an object is raised against the force of gravity
• Work done calculation against gravity

  • Force of 600 N (weight) x Vertical distance of 5 m = 3,000 J