| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.38 |
| Score | 0% | 68% |
Alternating current changes __________ many times each second.
direction |
|
resistance |
|
period |
|
frequency |
In contrast to the constant one-way flow of direct current, alternating current changes direction many times each second. Electricity is delivered from power stations to customers as AC because it provides a more efficient way to transport electricity over long distances.
Which of the following will help to prevent a short circuit?
resistor |
|
transistor |
|
diode |
|
fuse |
Fuses are thin wires that melt when the current in a circuit exceeds a preset amount. They help prevent short circuits from damaging circuit components when an unusually large current is applied to the circuit, either through component failure or spikes in applied voltage.
Which of the following converts electrical energy into another form of energy in an electrical circuit?
load |
|
AC source |
|
wiring |
|
DC source |
A load is a source of resistance that converts electrical energy into another form of energy. The components of a microwave, for example, are loads that work together to convert household electricity into radation that can be used to quickly cook food.
Capacitors connected in series produce __________ capacitance compared to capacitors connected in parallel.
less |
|
the same |
|
no |
|
more |
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 connected in series produce less capacitance than capacitors connected in parallel.
| 212.5 V | |
| 850 V | |
| 425 V | |
| 382.5 V |
Ohm's law specifies the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR.
V = \( I \times R \) = \( 8.5 \times 50 \) = 425 V