Lo stato di un gas è descritto da quattro grandezze: la massa, il volume, la temperatura e la pressione. Le trasformazioni dei gas definiscono il passaggio del gas da uno stato iniziale a uno stato finale: trasformazioni isòbare (pressione costante);...

Un campo elettrico variabile genera un campo magnetico variabile, che a sua volta genera un campo elettrico variabile e così via. In questo modo si propaga un’onda elettromagnetica, che trasporta energia e continua a propagarsi anche quando la...

Partendo dall’ipotesi della costanza di c, Einstein comprese che non esiste un tempo assoluto, cioè un tempo che scorre immutabile e identico in tutti i sistemi di riferimento. Due eventi che risultano simultanei in un dato sistema di riferimento...

Energy comes to Earth from the Sun in two main forms that we can use directly, heat and light. We use heat energy for solar heating and we transform the light energy into electrical energy. Solar heating is used for water heating systems as one...

La massa inerziale di un corpo e la sua massa gravitazionale sono direttamente proporzionali ed è possibile scegliere le loro unità di misura in modo che esse risultino uguali. Ciò fa sì che, in una data zona dello spazio, l’accelerazione di...

The 2009 Nobel Prize for Physics was awarded for two scientific achievements that have helped to shape the foundations of today’s networked societies. In 1966, Charles K. Kao made a discovery that led to a breakthrough in fibre optics. He carefully...

Like many of today’s great inventions, the microwave oven was a by-product of another technology. It was during a radar-related research project around 1946 that Dr. Percy Spencer, a self-taught engineer with the Raytheon Corporation, noticed...

During the Winter Olympics and other major figure skating championships, millions of figure skating fans watch their favourite figure skaters perform graceful programs on ice that usually include very rapid spins, which are often combined with jumps....

The work that first brought Newton to the attention of the scientific community was not a theoretical or even a mathematical effort; it was a prodigious technical achievement. In 1668, shortly before his appointment as Lucasian Professor, Newton...

Relativity begins with a modest question: how does your physics relate to my physics if we are moving relative to each other? Galileo gave one answer: we find exactly the same laws of mechanics if our relative speed is constant. Newton said the same...

In the early 1600s, Johannes Kepler proposed three laws of planetary motion. Kepler was able to summarize the carefully collected data of his mentor – Tycho Brahe – with three statements that described the motion of planets in a Sun-centered solar...

Light is part of the electromagnetic spectrum, which includes visible light, microwaves, radio waves, x-rays, and gamma gays. In the late 1600s, important questions were raised, asking whether light is made up of particles or waves. Sir Isaac Newton...

The complete break with classical physics comes with the realization that not just photons and electrons but all “particles” and all “waves” are in fact a mixture of wave and particle. It just happens that in our everyday world the particle...

As a rule, scientists display their talents either as theorists or as experimentalist, but not both. Einstein, Maxwell, and Gibbs, for example, were great as theorists but not creative as experimentalists, while Faraday and Rutherford, great as...

The Large Hadron Collider (LHC), the world’s largest and most powerful particle accelerator, is the latest addition to CERN’s accelerator complex. It mainly consists of a 27-kilometre ring of superconducting magnets with a number of accelerating...