The educational resource shows information about the coal: coal is a light, black substance which comes from the fossilization of vegetable matter. Coal is used as an industrial fuel, in power stations and in home heating. There are 4 types of coal: anthracite, bituminous coal, lignite and peat.You can see how they are formed in the following animation.

The educational resource shows information about the concept of chemical energy: chemical energy is what is produced in chemical reactions. An energy cell or a battery possess this type of energy. The gas burning in a cigarette lighter shows how the chemical energy contained in the gas is transformed into light and heat.

Energy from fossil fuels (coal, oil and natural gas) comes from substances which originated from the accumulation, millons of years ago, of large quantities of remains of living beings at the bottom of lakes and other sedimentary depressions. By clicking on the following controls you can learn more about each one of these fuels.

Concept of density. Performing calculations.

The area of the graph between the curve F and the X axis, represents the work carried out by the force between the two positions x0 and x. Review how to use the following visual and carry out the two proposed activities for a better understanding.

The educational resource shows a visual about the intensity of the electric field: What are the lines of force in a field created by two electric charges?

The educational resource shows a visual about the graphically represent the electric field: we use the concept of lines of force.

Concepts of analysis and interpretation of results within the scientific method

The educational resource shows a visual about gravitational potential energy: the calculation of gravitational potential energy is very easy for small heights.

Concept of attraction among masses

Experiment concept

Concept of harmonics

Concept of digital instruments

Buoyancy concept

The educational resource shows a visual about the equipotential surfaces: they are formed by all points with the same potential.

The educational resource shows a visual about the intensity of the electric field: a body's electric charge alters the space which surrounds it. The magnitude which measures this alteration at a determined point is the intensity of the electric field at this point.

Concept of data tables in a uniform movement

Diffraction concept

Forces can carry out work. The work done by a force is different if it has the same direction and orientation as the displacement, or if its direction is different.

In this educational resource you can check the next physical phenomenon: when there is a change of state in pure substances, the temperature remains constant.