Electronics Engineering :: Voltage and Current

Q.  What is the color code for a 220 resistor?

      A  . Red, Red, Brown, Gold

      B  . Orange, Orange, Black, Gold

      C  . Red, Red, Black, Gold

      D  . Red, Red, Brown, Silver

View Answer

Answer ::   B

Explanation ::

Resistor colour coding series:

Black 0
Brown 1
Red 2
Orange 3
Yellow 4
Green 5
Blue 6
Violet 7
Gray 8
White 9
None 20%
Silver 10%
Gold 5%

Therefore Red, Red, Brown, Gold
2 2 101 5%

= 22 x 10 = 220 ohm 5% (tolerance).

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 Q.  If 60 J of energy are available for every 15 C   of charge, what is the voltage?

      A  . 4 V

      B  . 60 V

      C  . 15 V

      D  . 0.25 V

View Answer

Answer ::   B

Explanation ::.

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 Q.  An atom's atomic number is determined by the number of:

      A  . neutrons minus protons

      B  . protons

      C  . electrons

      D  . neutrons

View Answer

Answer ::   B

Explanation ::.

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 Q.  a voltage will influence current only if the circuit is:

      A  . open

      B  . insulated

      C  . high resistance

      D  . closed

View Answer

Answer ::   D

Explanation ::.

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 Q.  Which resistive component is designed to be temperature sensitive?

      A  . Thermistor

      B  . Rheostat

      C  . Potentiometer

      D  . Photoconductive cell

View Answer

Answer ::   A

Explanation ::.

Q.  The battery symbol is:

      A  .

      B  .

      C  .

      D  .

View Answer

Answer ::   B

Explanation ::.

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 Q.  What type of switch is this?

      A  . push button

      B  . SPST

      C  . DPDT

      D  . SPDT

View Answer

Answer ::  D

Explanation ::.

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 Q.  Primary batteries, unlike secondary batteries, may be:

      A  . charged once

      B  . used once

      C  . recharged over and over

      D  . stored indefinitely

View Answer

Answer ::   B

Explanation ::.

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 Q.  In practical applications, battery voltage:
    A  . is restored as soon as disconnect occurs

      B  . is lowered as the load increases

      C  . may be stored indefinitely

      D  . will be reduced to zero as power is drawn

View Answer

Answer ::   B

Explanation ::.

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 Q.  The negative and positive charge symbols are assigned (in that order) to the:

      A  . proton and electron

      B  . electron and proton

      C  . atom and nucleus

      D  . electron and element

View Answer

Answer ::   B

Explanation ::.

Q.    voltmeter is used:

      A  . to measure current

      B  . in series with the circuit

      C  . in parallel with the circuit

      D  . to measure coulombs

View Answer

Answer ::   C

Explanation ::.

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 Q.  If the current in a circuit equals 0 A , it is likely that the

      A  . voltage is too high

      B  . resistance is too low

      C  . circuit has a short

      D  . circuit is open

View Answer

Answer ::   D

Explanation ::.

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 Q.  Current equals:

      A  .

      B  . coulombs × time

      C  .

      D  . voltage × time

View Answer

Answer ::  A

Explanation ::.

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 Q.  What are the unit and symbol for current?

      A  . Ampere,  A  

      B  . Coulomb, I

      C  . Ampere, Q

      D  . Ampere, I

View Answer

Answer ::   D

Explanation ::.

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 Q.  Which part of an atom has no electrical charge?

      A  . Electron

      B  . Neutron

      C  . Proton

      D  . All of the above

View Answer

Answer ::   B

Explanation ::.

Q.  Which voltage source converts chemical energy to electrical energy?

      A  . Electrical generator

      B  . Battery

      C  . Solar cell

      D  . Electronic power supply

View Answer

Answer ::   B

Explanation ::.

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 Q.  An example of potential energy is:

      A  . tea-kettle steam

      B  . a moving vehicle

      C  . the sun

      D  . a battery

View Answer

Answer ::   D

Explanation ::.

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 Q.  If 40 C of charge flow past a point in 20 s, what is the current?

      A  . 2A                                                   B  . 0.5A

      C  . 20A                                                 D  . 40 A

View Answer

Answer ::  

Explanation ::.

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Q. Batteries differ from fuel cells in that

      A  . a battery is a closed system

      B  . a battery uses hydrogen and oxygen to create electricity

      C  . a battery uses a polymer electrolyte membrane

      D  . none of the above

View Answer

Answer ::   A

Explanation ::.

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 Q.  The removal of a non-neutral subatomic particle converts the atom into a:

      A  . charged ion

      B  . nucleus

      C  . heavier element

      D  . compound

View Answer

Answer ::   A

Explanation ::.