Inductance and Capacitance

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Inductance and Capacitance

• INEL 4075 Chapter 7
• Dr. Sandra Cruz-Pol
• Professor
• Electrical Computer Engineering
• UPRM

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Capacitors
Capacitors store electrons in form of separated
charge or E field.
http//www.kpsec.freeuk.com/components/led.htm
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Capacitance, in Farads F

• The capacitance is
• The charge
• The current in a capacitor
• The voltage, cannot change instantaneously

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Capacitors

• Energy stored in capacitor
• Parallel and Series capacitors

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Electric Circuit
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Discharging a capacitor
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Charge/discharge Capacitor
Piezo-electric material
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Chip (integrated circuits)
The 555 timer regulator pin layout (from
http//www.doctronics.co.uk/555.htm)
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1k
C (mF) Frequency (Hz)
C1 .100 111
C2 .068 170
C3 .047 230
C4 .033 348
C5 .022 490
C6 .015 718
C7 .010 1,173
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What is a circuit Board?
Nodes?
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Myth Why is the Ocean Blue?

• FALSE The ocean is blue because the sky
  reflection on its surface.
• TRUE Water is blue.
• frequency spectra
• But you need a huge amount of it to really see
  its color.
• Look at a swimming pool as it gets deeper even
  on cloudy days.

http//ece.uprm.edu/pol/OceanBlue.html
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Myth 2

• FALSE Thomas Edison, greatest contributor to
  Electricity and systems used today.
• TRUE Nikola Tesla greatest contributor to
  Electricity.
• Invented ac motor,
• perfected dc motor,
• invented radio transmission, (wireless)
• designed Niagara Falls generator,
• distribution systems,
• fluorescence lamps,
• remote control, wireless,
• logic circuits,
• 3 phasic and many others.

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Inductors

• Store magnetic fields

Symbol
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Inductors

• Energy storage inductors store energy
• in the form of a magnetic field
• Series and parallel inductance
• Initial conditions of switch circuits

solenoid
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Inductance, in Henries H

• The inductance is
• The voltage in an inductor
• The current, cannot change instantaneously

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Inductors

• Energy stored in inductor
• Series and Parallel inductors

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Electro-magnet
Warning!! It can get HOT.
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Where to find this material?

• http//ece.uprm.edu/pol/cursos