| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.51 |
| Score | 0% | 70% |
This circuit component symbol represents a(n):
transformer |
|
potentiometer |
|
inductor |
|
fuse |
Resistors are used to limit voltage and/or current in a circuit and can have a fixed or variable resistance. Variable resistors (often called potentiometers or rheostats) are used when dynamic control over the voltage/current in a circuit is needed, for example, in a light dimmer or volume control.
You would measure the amount of resistance at a certain point in a circuit with a(n):
voltmeter |
|
ammeter |
|
potentiometer |
|
ohmmeter |
Resistance is opposition to the flow of current and is measured in ohms (Ω). An ohmmeter is used to measure the amount of resistance at a certain point in a circuit.
An amplifier is most similar in function to which of the following:
capacitor |
|
step-down transformer |
|
transistor |
|
step-up transformer |
An amplifier is a device that takes a small input signal and creates a larger output signal. This makes it most similar to a step-up transformer which takes a smaller input voltage and creates a larger output voltage.
| 1.5 A | |
| 1.65 A | |
| 1.35 A | |
| 3 A |
Ohm's law specifies the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit: V = IR.
Solved for current, I = \( \frac{V}{R} \) = \( \frac{120}{80} \) = 1.5 A
Using a fuse with a current rating higher than that required by a circuit:
makes the circuit less safe |
|
is recommended |
|
is required |
|
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.