| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.58 |
| Score | 0% | 72% |
Direct current flows from the __________ terminal of the voltage source to the __________ terminal.
negative, negative |
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positive, negative |
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negative, positive |
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positive, positive |
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.
A capacitor to an electronic circuit is like a _______________ to a house?
gate |
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driveway |
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safe |
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storage shed |
Capacitors store electricity and are used in circuits as temporary batteries. Capacitors are charged by DC current (AC current passes through a capacitor) and that stored charge can later be dissipated into the circuit as needed. Capacitors are often used to maintain power within a system when it is disconnected from its primary power source or to smooth out or filter voltage within a circuit.
Which of the following is not a characteristic of a step-up transformer?
the secondary voltage is higher than the primary voltage |
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has more turns in the secondary winding than in the primary winding |
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the primary voltage is higher than the secondary voltage |
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increases voltage |
As their names indicate, a step-up transformer is used to step up or increase voltage and a step-down transformer is used to step down or decrease voltage. In a step-up transformer, the secondary voltage is higher than the primary voltage and it has more turns in the secondary winding than in the primary winding.
| 222 W | |
| 440 W | |
| 660 W | |
| 220 W |
The ampere is a unit of measurement for:
power |
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current |
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inductance |
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energy |
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.