| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.48 |
| Score | 0% | 70% |
Which of these materials is not a good conductor of electricity?
air |
|
tin |
|
copper |
|
gold |
All conductors have resistance and the amount of resistance varies with the element. In general, metals make the best conductors of electricity and non-metals make the worst conductors of electricity.
Resistance and current are __________ proportional.
exponentially |
|
inversely |
|
not |
|
directly |
Resistance is opposition to the flow of current and is measured in ohms (Ω). One ohm is defined as the amount of resistance that will allow one ampere of current to flow if one volt of voltage is applied. As resistance increases, current decreases as resistance and current are inversely proportional.
A diode to an electronic circuit is like a _______________ to a city?
one-way street |
|
traffic light |
|
highway |
|
parking lot |
A diode allows current to pass easily in one direction and blocks current in the other direction.
Why is an insulator a poor conductor of electricity?
an insulator is made of organic material |
|
an insulator has many free electrons |
|
an insulator is made of inorganic material |
|
an insulator has few free electrons |
Insulators have valence shells that are more than half full of electrons and, as such, are tightly bound to the nucleus and difficult to move from one atom to another.
A capacitor to an electronic circuit is like a _______________ to a house?
driveway |
|
gate |
|
storage shed |
|
safe |
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.