A capacitor offers infinite resistance at steady state because, in a DC (direct current) circuit, once it is fully charged, it acts as an open circuit to the steady flow of current. This occurs because a capacitor charges and stores electrical energy in the form of an electric field between its plates. As the capacitor … Read more
A light dependent resistor (LDR), also known as a photoresistor or photocell, is a type of resistor whose resistance decreases with increasing incident light intensity. This change in resistance is due to the interaction of light photons with the semiconductor material within the LDR. When exposed to light, more photons are absorbed by the semiconductor, … Read more
In electronic circuits, it is common practice to earth (ground) one of the two plates of a capacitor for several reasons. One primary reason is to establish a stable reference point for voltage levels within the circuit. By grounding one plate of the capacitor, this plate is connected to the earth potential, which is typically … Read more
A resistor can become non-ohmic, meaning it does not obey Ohm’s law (V = IR), due to various factors that alter its resistance with changes in voltage or current. One common cause is temperature dependency. Resistors made from materials whose resistivity changes with temperature can exhibit non-ohmic behavior. For example, as the temperature of a … Read more
Resistors resist electricity or current flow through the principle of resistivity, which is an intrinsic property of the material from which they are made. When current flows through a resistor, the electrons collide with atoms in the resistor material, resulting in a transfer of energy. This interaction impedes the flow of electrons and converts electrical … Read more
Variable resistors, also known as potentiometers or rheostats, have various uses across different applications. One common use for a variable resistor is in electronic circuits where precise control over resistance is necessary. They are often employed to adjust the voltage levels in a circuit, thereby controlling the amount of current flowing through specific components. This … Read more
A current limiting resistor is essential when driving an LED to ensure that the LED operates within its safe current range and does not exceed its maximum rated current. LEDs are current-driven devices, meaning their brightness and longevity are directly influenced by the current flowing through them. While LEDs do have a forward voltage drop … Read more
Resistors are passive electronic components that do not have polarity. Unlike components such as capacitors or diodes, which have specific orientations for their positive and negative terminals, resistors can be connected in any direction within a circuit without affecting their functionality. This is because resistors function based on the flow of current through them and … Read more
A MOSFET can be considered a voltage-controlled resistor under certain conditions where its drain-source resistance (R_DS(on)) varies with the gate-source voltage (V_GS). In linear operation, particularly in the ohmic region (when V_DS is small compared to V_GS – V_th), the MOSFET behaves similarly to a variable resistor whose resistance changes with the applied gate-source voltage. … Read more
A variable resistor, also known as a potentiometer or rheostat depending on its specific design, serves the function of adjusting resistance within an electronic circuit. Its primary role is to provide a variable resistance that can be manually adjusted to control voltage levels, current flow, or signal amplitude. This adjustability allows for precise tuning of … Read more