| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.41 |
| Score | 0% | 68% |
Using a fuse with a current rating higher than that required by a circuit:
is required |
|
makes the circuit less safe |
|
is recommended |
|
makes no difference |
A fuse is a type of low resistance resistor that stops current flow in a circuit in response to a larger than intended electric current flow. Using a fuse with a higher current rating than required by a circuit is less safe as it could potentially allow overcurrent and risk a fire or heat-related equipment damage.
Which of the following is not true about a line drop?
it is caused by resistance |
|
it is addressed by raising current and lowering voltage across the ransmission line |
|
it is a decrease in voltage between two points on a line |
|
it is addressed by raising voltage and lowering current across the transmission line |
Electricity is delivered from power stations to customers as AC because it provides a more efficient way to transport electricity over long distances. A line drop is a decrease in voltage between two points on an electrical transmission line due to resistance in the line. A lower current and higher voltage across the line will help compensate for the line drop.
The joule is a unit of measurement for:
resistance |
|
capacitance |
|
power |
|
energy |
The joule is a unit of measurement for energy.
Silver and gold are among the most highly conductive elements. Why is copper used much more often as a conductor in electrical circuits?
silver and gold are brittle |
|
copper is durable and relatively cheap |
|
silver and gold are costly |
|
all of these |
All conductors have resistance and the amount of resistance varies with the element. But, resistance isn't the only consideration when choosing a conductor as the most highly conductive elements like silver and gold are also more expensive and more brittle than slightly less conductive elements like copper. A balance needs to be struck between the electrical qualities of a material and its cost and durability.
| 60 Ω | |
| 61.5 Ω | |
| 54 Ω | |
| 63 Ω |
Ohm's law specifies the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR.
Solved for resistance, R = \( \frac{V}{I} \) = \( \frac{450}{7.5} \) = 60 Ω