When an undulatory movement comes across an obstacle which prevents its propagation and does not absorb its energy, the waves change direction, they are reflected.

Los cables conductores ofrecen resistencia al paso de la corriente eléctrica.

The residual current circuit breaker (RCCB) is one of the elements of a consumer unit. The following visual explains its function.

Forces are represented by means of vectors. A vector is an oriented sector. The following animation representes the characteristics of a vector.

El ODE muestra una escena interactiva donde aparece una gráfica fuerza/ desplazamiento correspondiente a la acción de una fuerza sobre un objeto. Se permite variar la fuerza aplicada y el desplazamiento que provoca con el objeto de calcular el trabajo que realiza dicha fuerza.

Renewable energy sources are those which after being used can be regenerated naturally or artificially. The following pictures are graphic examples rof enewable energy sources.

El principio de relatividad de Galileo enuncia que desde cualquier sistema de referencia inercial se observan las mismas leyes físicas (desde todos ellos se miden las mismas fuerzas) .

If at relativistic speeds bodies decrease in length, would it be possible to shut a large rocket which was travelling at the speed of light in a hangar? The answer to this question constitutes a "relativistic paradox".

Los resultados de las medidas realizadas en los experimentos suelen agruparse, para que podamos verlos "de un vistazo". Las tablas de datos constituyen una forma habitual de registrar las medidas realizadas en una investigación científica.

Imagine that a wave passes from a deeper zone to another shallow zone, or vice versa. There will be refraction.

Un rayo de luz atraviesa un medio, una parte se refleja y otra se refracta

Cuando un rayo de luz atraviesa una lámina de vidrio, se refracta. En determinadas circunstancias puede producirse una reflexión total

¿A cuántos radianes por segundo va la bola azul?

¿A cuántos radianes por segundo va la bola azul?

Angles can be measured with sexagesimal degrees. A right angle is equal to 90 degrees. Radians are another way of measuring angles.

Una de las formas de expresar los ángulos son los grados sexagesimales. Un ángulo recto tiene 90 grados sexagesimales. Otra manera de expresar la magnitud de un ángulo son los radianes.

The radioactive constant or decay constant, is a coefficient of proportionality which relates the atoms which disappear in a period of time t, with the initial atoms for each radioactive nuclide.

The activities of the isotopes formed at each stage of the radioactive series are equal to each other after some time. It is then said that radioactive equilibrium has been reached.

Radiation emitted by radioactive bodies.The radiation emitted by radioactive substances behaves differently when it passes through electric and magnetic fields.

The activity of a sample of a radioactive substance is the number of nuclei which disappear per unit of time and represents the speed of decay.