EE notes

• What is the relative permittivity of vacuum?

  1
• What is the SI unit of capacitance?

  • farad
  • ohm
  • henry
  • coloumb
• What is the absolute permittivity of air?

  8.854x10^-12
• Capacitor is prefered for high frequency application?

  • mica capacitor
  • electrolytic capacitor
  • air capacitor
• In order to increase the capacitance of parallel plate capacitor, one should introduce between the plates, a sheet of

  • Mica
  • copper
  • tin
  • steel
• Which of the following dielectric materials has the biggest value of DIELECTRIC STRENGTH?

  • Mica
  • Oil
  • Paper
  • Air
• What is the unit of absolute permittivity?

  • Joule per coulomb
  • newton-meter
  • Farad per meter
  • farad per coulomb
• In electric iron, what type of insulating material used?

  • mica
  • porcelain
  • air
• Which capacitors are maily used in RADIO FREQUENCY turning?

  • Paper type
  • Air type
  • Mica type
  • electrolytic type
• Which one is stored in a capacitor?

  • voltage
  • charge
  • current
  • power
• Unit of FIELD INTENSITY?

  • newton/couloumb
  • newton/meter
  • coulomb/newton
  • coulomb/square meter
• Type of dielectric is used in HIGH VOLTAGE TRANSFORMERS?

  • Porcelain
  • Oiled paper
  • Mica
  • Paraffin
• Type of capacitors is used only on DC CIRCUITS?

  • Electrolytic
  • Mica
  • Ceramic
  • Air
• A multi-plate capacitors has 7 PLATES, then how many capacitors are there?

  • 6 Capacitors in parallel
  • 6 Capacitors in series
  • 7 Capacitors in series
  • 7 Capacitors in parallel
• What is the charge of a test charge?

  • -1C
  • +1C
  • zero
  • infinite
• What is the relative permittivity of free space?

  • 1
  • 9x10^9
  • 8.854x10^-12
  • 1.6x10^-19
• What is the SI unit of flux density?

  • Tesla
  • Weber/meter
  • Newton per weber
  • Amper turn per meter
• Which one is a ferromagnetic materials?

  • Lead
  • bismuth
  • iron
  • water
• What is SI unit of PERMEABILITY?

  • Henry/meter
  • Henry
  • Unitless
  • 1/Henry
• In electric irons, what type insulating material used?

  • paper
  • mica
  • paraffin
  • rubber
• What kind of field is PRODUCED by a DC CURRENT?

  • magnetic field
  • electric field
  • gravitational field
  • electromagnetic field
• At an audio frequency range (about 20 Hz to 20 kHz), what type of inductors is commonly used?

  • air core
  • toroidal
  • solenoid
  • reactor
• A bar magnet has how many poles?

  • two poles
  • four poles
  • no poles
  • one poles
• What is the SI unit of RELUCTANCE?

  • AT
  • AT/WB
  • N/Wb
  • AT/m
• Which of the following Material groups, is the eddy current loss in decreasing order?

  • wood,aluminum,iron
  • aluminum,iron,wood
  • iron,wood,aluminum
  • iron,aluminum,wood
• Magnetic flux of 1 WEBER has how many lines of forces?

  • 10^8
  • 10^12
  • 10^14
  • 10^6
• Has the lowest eddy current loss?

  • laminated once
  • air core
  • metallic core
  • insulated core
• Five carbon-zinc cells in series have an output of

  • 11V
  • 7.5V
  • 1.5V
  • 5.0V
• How do you call a cell that canmot be recharged?

  • primary cell
  • wet cell
  • dry cell
  • secondary cell
• A dry cell is a modication on which of the following type ?

  • lechanche cell
  • deniell cell
  • edision cell
  • lead-acid cell
• What is the usual ampere-hour efficiency of a lead acid cell?

  • 90%
  • 50%
  • 70%
  • 25%
• How do you call the POSITIVE ELECTRODE of a battery?

  • anode
  • voltaic node
  • cathode
  • base terminal
• The ampere-hour capacity of an INDUSTRIAL BATTERY is based on how many hours if discharged?

  • 8 hours
  • 12 hours
  • 24 hours
  • 6 hours
• The output voltage of a lead-acid cell is___

  • 1.25V
  • 2.1V
  • 1.35V
  • 6V