WORK, POWER AND ENERGY

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WORK, POWER AND ENERGY
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WORK

• Work is done ONLY when a force moves an object
• Work is a force acting over a distance
• If an object does NOT move when a force is
  applied to it, no work is done

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WORK
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POWER

• HOW FAST work is being done
• The same amount of work done faster will produce
  more power
• Power is the rate at which work is done
• Power is the amount of work done in a certain
  amount of time

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POWER
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ENERGY

• Energy is the ability to do work
• Doing work uses energy
• An object can gain energy if work is done on it

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FORMS OF ENERGY

• MECHANICAL-energy relating to moving objects
• HEAT-energy related to the vibration of the
  particles that make up an object
• CHEMICAL-energy related to the bonds that hold
  particles together
• ELECTROMAGNETIC-energy related to moving
  electrical charges
• NUCLEAR-energy related to the decay of the
  nucleus of atoms

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ENERGY CONVERSION

• All forms of energy can be converted into other
  forms
• Energy from the sun can become electrical energy
• Moving water can turn turbines and produce
  electrical energy

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LAW OF CONSERVATION OF ENERGY

• Energy cannot be created or destroyed by ordinary
  means

All of the energy in the universe has been
present since the beginning of time
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POTENTIAL ENERGY

• The energy stored in an object because of its
  position
• The work done to move an object to a new position
  is stored in the object as potential energy
• Potential energy stored in an object that will
  move because of gravity is called gravitational
  potential energy

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POTENTIAL ENERGY
MEASURED IN NEWTONS (N)
MEASURED IN METERS (m)
REMEMBER, WEIGHT IS MASS X GRAVITY
MEASURED IN JOULES (J)

• The more mass an object has, the
• more potential energy it has
• The higher an object is raised, the
• more potential energy it has
• The more work is done to an object,
• the more potential energy it has

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KINETIC ENERGY

• The energy an object has because it is moving is
  kinetic energy
• A moving object turns it potential energy into
  kinetic energy as it moves
• When an object uses up all of its potential
  energy, it will quit moving

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KINETIC ENERGY
MEASURED IN JOULES (J)
MEASURED IN KILOGRAMS (kg)
MEASURED IN METERS PER SECOND (m/s)
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KINETIC ENERGY

• The more mass an object has, the more kinetic
  energy it has
• The faster an object is going, the more kinetic
  energy it has
• The more potential energy an object starts with,
  the more kinetic energy it can release