Contact Points and Light Bulbs

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Contact Points and Light Bulbs

• Physics First
• Unit 1 Electricity

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Contact Points

• All electrical points have contact points
• Contact points- allow electrical current to flow
• Inside the device there is a pathway (without
  breaks) so current can flow

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Contact Points

• All devices must have at least 2 contact points
  (some have more)
• One point allows current to flow in while the
  other allows current to flow out
• Contact points must be separated by some
  insulator

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Anatomy of a Light Bulb

• 3. filament wire- current passes through and
  creates heat which turns to light
• 4 and 5- contact wires that connect to filament
• 9 and 11- outside contact points insulated by 10
• 8- wire connected to inside contacts

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Anatomy of a Light Bulb

• 1. Glass bulb- protector
• 2. Inside gas- does not allow the filament to
  burn out
• 6. Support wires- no electrical purpose
• 7. Stem- glass mount

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Symbols

• Resistor- (light bulb, motor, buzzer) device that
  a current can cross

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Symbols

• Wire
• Battery

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Symbols

• When a switch is opened or closed we must show it
  in our circuit diagrams

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