| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.25 |
| Score | 0% | 65% |
Why is an insulator a poor conductor of electricity?
an insulator is made of organic material |
|
an insulator has few free electrons |
|
an insulator is made of inorganic material |
|
an insulator has many 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.
Which of the following is a characteristic of batteries connected in series?
total voltage equals the average of the individual battery voltages |
|
total voltage equals the sum of the individual battery voltages |
|
the positive terminal of one battery is connected to the positive terminal of the next |
|
two connections are made between each adjacent battery |
You can multiply the voltage or the current supplied by individual batteries by connecting them together either in series or in parallel. The characteristics of batteries connected in series are that total voltage equals the sum of the individual battery voltages, total current equals the average of the individual battery currents, the positive terminal of one battery is connected to the negative terminal of the next, and one connection is made between each adjacent battery.
| 60 Ω | |
| 66 Ω | |
| 120 Ω | |
| 61 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 = \( \frac{V}{I} \) = \( \frac{570}{9.5} \) = 60 Ω
Which of the following is not true about a line drop?
it is addressed by raising voltage and lowering current across the transmission line |
|
it is addressed by raising current and lowering voltage across the ransmission line |
|
it is caused by resistance |
|
it is a decrease in voltage between two points on a 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.
Electricity cannot flow...
through a circuit with resistance |
|
through a circuit under load |
|
through an open circuit |
|
through a closed circuit |
An electrical circuit is a path through which electricity flows. This path contains one or more components that create a load (something that is using electricity) and that load acts as resistance to the passage of electricity through the circuit. Electricity can only flow through a circuit when the path is closed and cannot flow through an open circuit.