current, voltage, resistance and ohm's law

• causes current to flow

  voltage
• the charge (electron) "pusher"

  voltage
• voltage sources

  battery, generator, outlets
• symbol for voltage

  v
• unit for voltage

  volts v
• Italian physicist

  known especially for the invention of the electrochemical cell, aka battery in 1800

  alessandro volta
• invented the battery

  alessandro volta
• when did alsessandro volta invented battery


  1800
• Power utilities use large generators to provide the

  120V that is delivered to your home outlets.
• flow of charge (electrons) within a conductor or how fast charge is moving.


  current
• charge will only flow if there is a voltage source

  potential difference
• symbol for current

  I
• unit for current

  amps a
• One of the main discoverers of electromagnetism.

  andre ampere
• effect of 0.001 amps to people

  can be felt
• effect of 0.005 amps to people


  painful
• effect of 0.010 amps to people

  involuntary muscle spasms
• effect of 0.015 amps to people

  loss of muscle control
• effect of 0.070 amps to people

  if through heart, serious injury, likely fatal it lasts more than 1 second
• opposes the push from the voltage source

  resistance
• affects the speed of the current

  resistance
• symbol for resistance

  r
• unit for resistance

  ohms
• determined that there is a direct proportionality between the voltage applied across a conductor and the electric current.

  georg ohm
• is a direct proportionality between the voltage applied across a

  conductor and the electric current.

  ohm's law
• If the voltage in a circuit increases, the current

  will increase.
• If the voltage in a circuit decreases, the current

  will decrease.
• voltage and current has a direct or proportional relationship
• If the resistance in a circuit increases, the current will decrease.
• If the resistance in a circuit decreases, the current will increase.
• resistance and current has an inversely proportional relationship
• State the relationship between current, voltage, and resistance.

  ohm's law
• formula for ohm's law


  V=IR
• states that, in an electrical circuit, the current passing through most materials is directly proportional to the potential difference applied across them.

  ohm's law
• When V is constant: I decreases as R increases.
• When V is constant: I increases as R decreases.
• If R doubles, I is reduced by half.
• If R is reduced to ¼, I increases by 4.
• The kilowatt hour (kWh) is a unit commonly used for large amounts of electrical work or energy.
• When current flows in a resistance, heat is produced

  from the friction between the moving free electrons and

  the atoms obstructing their path.