## Electric current: How charges flow through a conductor

In this lesson you will learn the basics of the electric current, i.e. the definition, its physical meaning and unit.

Electromagnetic phenomena and their applications

- 1
Lesson ## Electric current: How charges flow through a conductor

In this lesson you will learn the basics of the electric current, i.e. the definition, its physical meaning and unit.

Video ## Electric Current explained simply in 7 minutes!

In this video you will learn the basics of the electric current, i.e. the definition, its physical meaning and unit.⠀

## Related formulas

Formula ## Electric current (definition)

`$$ I ~=~ \frac{Q}{t} $$` - 2
Lesson ## Voltage: How it is created by charge separation!

Here you will learn what voltage is, how it is generated by charge separation, how a voltage source can be created, and what voltage has to do with current.

Video ## Voltage explained simply in 10 minutes!

Here you will learn what voltage is, how it is generated by charge separation, how a voltage source can be created, and what voltage has to do with current.

- 3
Lesson ## Ohm's law: Formula, Graph and 3 Easy Examples

Here you learn Ohm's law, how it is expressed as a formula and as a graph. We also look at three examples.

Video ## Ohm's law explained simply in 13 minutes!

Here you will learn how to recognize Ohm's Law in a U-I diagram and how to apply the associated URI formula. Three examples are covered.

## Related formulas

Formula ## Ohm's law (resistance, voltage, current)

`$$ U ~=~ R \, I $$` - 4
Lesson ## Plate Capacitor: Voltage, Capacitance and Eletric Force

Here the plate capacitor is simply explained. With the help of the capacitor you will learn about the electric voltage, electric field and electric capacitance and how to calculate them for a plate capacitor.

Video ## Plate Capacitor explained simply in 7 minutes!

Here the plate capacitor is simply explained. With the help of the capacitor you will learn about the electric voltage, electric field and electric capacitance and how to calculate them for a plate capacitor.

## Quests with solutions

Exercise with solution ## Create a plate capacitor with a certain capacitance

In this exercise (with solution) you have to calculate the distance between the capacitor plates for a given capacitance and and than use relative permittivity.

Exercise with solution ## Charge in a thundercloud

The exercise teaches you how to calculate the charge of a thundercloud using the capacitance and E-field in the plate capacitor.

Exercise with solution ## Capacitor with and without dielectric in comparison

In this exercise with solution about the plate capacitor, the capacitance, voltage and energy must be compared with and without dielectric.

## Related formulas

Formula ## Plate capacitor (force, voltage, charge, distance)

`$$ F ~=~ q \, \frac{U}{d} $$`Formula ## Plate Capacitor (Capacitance)

`$$ C ~=~ \varepsilon_0 \, \varepsilon_{\text r} \, \frac{A}{d} $$`Formula ## Plate capacitor (energy, electric field)

`$$ W_{\text{e}} ~=~ \frac{1}{2} \, \varepsilon_0 \, \varepsilon_{\text r} \, V \, E^2 $$`Formula ## Plate capacitor (electric field, voltage, distance)

`$$ E ~=~ \frac{U}{d} $$`