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Flashcards in Direct Current Deck (25)
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1

In a DC circuit, current flows

A. From a negative to positive
B. From positive to negative
C. Slower if the voltage is reduced in a circuit
D. Faster if the resistance is increased in the circuit

A. From a negative to positive

2

The three components needed in a electrical circuit are the?

A. Path, volts, and power
B. Current, path, and load
C. Power source, path, and load
D. Switch, power source, and load

C. Power source, path, and load

3

On a direct current power source

A. Black represents negative and green represents positive
B. Black represents positive and the green represents negative
C. Red represents positive and the black represents negative
D. Red represents negative and the black represents positive

C. Red represents positive and the black represents negative

4

Increasing the length of the path of an electrical circuit will?

A. Decrease the total circuit resistance l
B. Increase the current
C. Increase resistance
D. Increase voltage

C. Increase resistance

5

The load in a electrical circuit is used to?
A. Crate electrical energy
B. Convert electrical energy to heat, light, or magnesium
C. Convert mechanical energy to electrical energy
D. Create heat, light, magnetism

B. Convert electrical energy to heat, light, or magnetism

6

A switch in a electrical circuit is used to?
A. Control current to a load
B. Control the resistance of an electrical load
C. Control the flow of voltage
D. Control the wattage of a load

A. Control current to a load

7

When placed in a electrical circuit, a open switch will?

A. Make the path to a load
B. Break the path to a load
C. Have no effect on the path to the load
D. Will temporarily interrupt voltage flow

B. Break the path to a load

8

When placed in a electrical circuit, a closed switch will?

A. Make the path to a load
B. Break the path to a load
C. Have no effect on the path to a load
D. Will temporarily interrupt voltage flow

A. Make the path to a load

9

An example of a manually operated switch would be a

A. Temperature control
B. Pressure control
C. Defrost timer
D. Toggle switch

D. Toggle switch

10

An example of a automatically operated switch would be a

A. Lever type
B. Push button
C. High pressure control
D. Single pole double throw toggle switch

C. High pressure control

11

On what type of electrical circuit can ohm's law be used
A. A inductive circuit
B. A capacitive circuit
C. A resistive circuit
D. A inductive, capacitive, and a resistive circuit

C. A resistive circuit

12

Which is used to find the amperage using ohm's law

A. E=IR
B. R=I/R
C. R=E/I
D. I=RE

B. I=E/R

13

Which is used to find resistance using ohm's law?
A. E=IR
B. R=I/R
C. R=E/I
D. I=RE

C. R=E/I

14

Which is used to find voltage using ohm's law?
A. E=IR
B. R=I/R
C. R=E/I
D. I=RE

A. E=IR

15

Which is used to find power using Watt's law?
A. P=E/R
B. P=EI
C. P=E2/I
D. P=E/R

B. P=EI

16

Which is used to find power using watt's law?

A. P=E/I
B. P=E2/I
C. P=I2R
D. P=E/R

C. P=I2R

17

When three 15 ohm resistors are connected in series using a 120v power source, what is the total amperage of the circuit?

A. 8 amps
B. 3.2 amp
C. 2.7 amps
D. 375 mili-amps

C. 2.7 amps

18

When two 20 ohm resistors are connected in parallel and the source voltage is 240 volts, what is the total amperage of the circuit?

A. 12 amps
B. 24 amps
C. 3 amps
D. 10 amps

B. 24 amps

19

When a 24 volt power supply is used in a circuit with 12 ohms of resistance, what is the total power rating of the circuit?

A. 2 watts
B. 288 watts
C. 24 watts
D. 48 watts

D. 48 watts

20

What is the total resistance of a circuit when a 5 ohm resistor, a 10 ohm
Resistor, and a 15 ohm resistor are wires in parallel with each other?

A. 30
B. 15
C 4.55
D. 2.75

D. 2.75

21

In a series circuit, which would be true?

A. Current is the same throughout the circuit
B. Current increases as loads are added
C. Resistance decreases as loads are added
D. Voltage increases as loads are added

A. Current is the same throughout the circuit

22

In a series circuit which would not be true?

A. Resistance decreases as loads are added
B. Resistance is increased as loads are added
C. Voltage drops across loads are wired in series
D. Current is the same throughout the circuit

A. Resistance decreases as loads are added

23

In a series circuit that is using a electrical heater as the load, what would cause an increase in circuit current

A. A decrease in resistance
B. An increase in resistance
C. A decrease in voltage
D. A burnt contact

A. A decrease in resistance

24

In a parallel circuit, which would be true?

A. Voltage is the same across each load
B. Current is always the same across each load
C. Total resistance increases as loads are added
D. Voltage increases as loads are added

A. Voltage is the same across each load

25

In a parallel circuit, which would be true?

A. Total resistance decreases as loads are added
B. Voltage is the same across each load
C. Current decreases as loads are added
D. Current increases as loads are added

D. Current increases as loads are added