Module 3: Electrical Fundamentals - Capacitance

The amount of charge a capacitor can store at a given voltage. It depends on the physical characteristics of the capacitor, including the area of the plates, the distance between them, and the dielectric material used.

The larger the area of the plates, the greater the capacitance. This is because more charge can be stored on larger plates.

Capacitance increases as the distance between the plates decreases. This is because the electric field between the plates is stronger when they are closer together.

A material that is a poor conductor of electricity but can support an electrostatic field. It's like an insulator for electricity.

A non-conducting material that reduces the electric field between the capacitor plates, increasing capacitance.

Connecting capacitors in parallel increases the total plate area, leading to a larger total capacitance. You simply add up the individual capacitances.

Connecting capacitors in series increases the effective distance between the plates, decreasing the total capacitance.

The formula for calculating total capacitance of capacitors connected in parallel is to simply add up the individual capacitances.

A capacitor is an electrical component that stores electrical energy in an electric field. It consists of two conductive plates separated by an insulating material called a dielectric.

Capacitors are designed to increase charge storage by using plates instead of single conductors. This allows for a greater surface area, which in turn leads to greater charge capacity.

The dielectric material between the plates of a capacitor prevents the flow of direct current (DC) while allowing the electric field to build up to full potential.

When a voltage is applied to a capacitor, electrons flow from one plate to the other, creating an electric field between the plates. This process is called charging the capacitor.

Once a capacitor is fully charged, the voltage across the plates equals the applied voltage. At this point, the current flow ceases, and the capacitor acts as an open circuit for DC.

When the voltage across a capacitor reverses, the plates discharge and then re-charge with the opposite polarity. Again, current flow stops once the capacitor reaches the applied voltage.

Unlike DC, alternating current (AC) causes a capacitor to continuously charge and discharge, resulting in a constant current flow through the wires connected to the plates. However, electrons do not actually transfer across the dielectric.

Since a capacitor allows for a continuous flow of current in the wires connecting to its plates when AC is applied, it is said to 'pass' AC.

The time it takes for the voltage across a capacitor to reach 63.2% of the source voltage in an RC circuit.

TC = R x C, where:

• TC is the time constant in seconds.
• R is the resistance in ohms.
• C is the capacitance in farads.

In order for a capacitor to charge to 100% of the source voltage in an RC circuit, it takes 5 times the time constant (5 x TC).

It takes 1 time constant (TC) for a capacitor to discharge by 63.2% of its initial voltage in an RC circuit.

In order for a capacitor to completely discharge in an RC circuit, it takes 5 times the time constant (5 x TC).

The value of resistance (R) and capacitance (C) determines the time constant (TC) in an RC circuit.

An RC circuit with higher resistance and capacitance values will have a longer time constant.

An RC circuit with lower resistance and capacitance values will have a shorter time constant.

The tolerance of a capacitor indicates the percentage deviation from the nominal value that is acceptable. It signifies how much the actual capacitance can vary from the stated value.

The value of capacitance in a capacitor can be expressed in various units, with picofarads (pF) being a common one. 1 picofarad is equal to 10^-12 farads.

The tolerance value is expressed as a percentage of the nominal value of the capacitor. For example, a capacitor with a 10% tolerance can have a capacitance value that is 10% higher or lower than the stated value.

A variable capacitor is a type of capacitor where its capacitance can be adjusted by changing the distance between its plates.

Variable capacitors are primarily used for tuning radio receivers and other electronic circuits.

A trimmer capacitor is a type of variable capacitor that allows for fine-tuning adjustments.

The charging of a capacitor in an RC circuit follows an exponential curve. This means the voltage across capacitor plates increases gradually over time, eventually reaching a steady state.

The amount of time it takes for a capacitor to charge is influenced by the values of resistance and capacitance in the circuit.

The process where a capacitor stores electrical energy in an electric field.

The process where a capacitor releases stored electrical energy.

The voltage across a capacitor after one time constant (TC) during the charging process.

The voltage across a capacitor after one time constant (TC) during the discharging process.

Connecting capacitors side-by-side increases their total capacitance.

Connecting capacitors end-to-end decreases their total capacitance.

The voltage across each capacitor in a parallel connection is the same.

The capacitance of a capacitor is measured in Farads (F). It represents the amount of electrical charge a capacitor can store at a given voltage. Basically, how much energy it can hold.

Increased plate area allows for more charge to accumulate on the plates, leading to a higher capacitance. Think of it as having more space to store charge.

The distance between the plates is inversely proportional to capacitance. That means decreasing the distance between the plates will increase the capacitance. Imagine squeezing the container to make it smaller, it holds less water.