CP7&8 Energy & Forces

• What is the capacity to do work called?

  Energy
• What are the units of energy?

  Joules
• What is the symbol for kilojoules?

  kJ
• How many joules are in one kilojoule?

  1000 J
• What does work done refer to?

  The energy transferred by a force
• How do you calculate work done?

  Work done = force x distance
• What is the formula for work done in symbols?

  E = F x d
• What are the units for work done?

  Joules
• What is power defined as?

  The rate of energy transfer
• What is the unit of power?

  Watts
• How is one watt defined?

  1 W = 1 joule per second
• How do you calculate power?

  Power = work done / time
• What are the units for power?

  Watts
• What is a contact force?

  A force that acts when two objects touch
• Can you name examples of contact forces?

  Normal force, friction, upthrust
• What is a non-contact force?

  A force that acts at a distance
• Can you name examples of non-contact forces?

  Gravity, magnetism, electrostatic force
• What happens when A applies an action force to B?

  B applies a reaction force of same size
• What is a force field?

  The area around an object affecting others
• What is a magnetic field?

  The area of magnetic force around a magnet
• What is an electric field?

  The area of electrostatic force around a charged object
• What are vectors?

  Arrows that show size and direction
• What is a free body diagram?

  A diagram showing all the forces on an object
• What do vector diagram arrows represent?

  Size and direction of a force
• What is a scale diagram?

  A diagram drawn on graph paper for forces
• What is a resultant force?

  The force left over when forces cancel out
• How do you create a resultant force diagram?

  Draw arrows for two forces, add a parallelogram
• What does resolving forces mean?

  Breaking a force into horizontal and vertical components
• What are component forces?

  The vertical and horizontal forces from a diagonal force
• What is a resolving forces diagram?

  A diagram showing a force and its components