| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.69 |
| Score | 0% | 74% |
Direct current flows from the __________ terminal of the voltage source to the __________ terminal.
negative, negative |
|
negative, positive |
|
positive, positive |
|
positive, negative |
Direct current flows in only one direction in a circuit, from the negative terminal of the voltage source to the positive. A common source of direct current (DC) is a battery.
The ampere is a unit of measurement for:
inductance |
|
energy |
|
current |
|
power |
Current is the rate of flow of electrons per unit time and is measured in amperes (A). A coulomb (C) is the quantity of electricity conveyed in one second by a current of one ampere.
The hertz is a unit of measurement for:
inductance |
|
energy |
|
power |
|
frequency |
The hertz is a unit of measurement for frequency.
Voltage and current are __________ proportional.
directly |
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inversely |
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indirectly |
|
not |
Voltage (V) is the electrical potential difference between two points. Electrons will flow as current from areas of high potential (concentration of electrons) to areas of low potential. Voltage and current are directly proportional in that the higher the voltage applied to a conductor the higher the current that will result.
| 5 A | |
| 18 A | |
| 13.5 A | |
| 9 A |
Ohm's law specifies the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR.
Solved for current, I = \( \frac{V}{R} \) = \( \frac{90}{10} \) = 9 A