相关论文: Thump, ring: the sound of a bouncing ball
In the present paper, we investigate the properties of the sound generated by rubbing two objects. It is clear that the sound is generated because of the rubbing between the contacting rough surfaces of the objects. A model is presented to…
Following his observation the author has described in the papers [1] to [4] the formation of a Lightning Ball (LB)with the help of a new theory of symmetry breaking of the vortex ring. In the frame of this theory he emphasizes the…
When a bubble of air rises to the top of a highly viscous liquid, it forms a dome-shaped protuberance on the free surface. Unlike a soap bubble, it bursts so slowly as to collapse under its own weight simultaneously, and folds into a…
A trimer is an object composed of three centimetrical stainless steel beads equally distant and is predestined to show richer behaviours than the bouncing ball or the bouncing dimer. The rigid trimer has been placed on a plate of a…
We present a comprehensive theory on the formation of ball lightning, a luminous sphere sometimes observed after normal lightning. In a ball lightning event, a relativistic electron bunch can be produced by the stepped leader of lightning…
In the superconducting medium the circular current supported by its own magnetic field can exist giving rise to the possible underlying mechanism for the ball lightning.
The ball lightning is supposed to be a shock wave of a point explosion frozen with electrostriction forces of the internal strong laser discharge. The life time of the ball with modest parameters is calculated.
The difference between "beating" and "pushing" results in the perception that a push just makes the object move as a whole, while a beat produces also a sound. Through a detailed analysis of the physics underlying such everyday experiences,…
A vacuum-powered device that shoots ping pong balls at high subsonic speeds has been used for physics demonstrations for more than a decade. It uses physics that are easily understood by students, even though its operation is not…
We call a system bouncing ball billiard if it consists of a particle that is subjected to a constant vertical force and bounces inelastically on a one-dimendional vibrating periodically corrugated floor. Here we choose circular scatterers…
Ball lightning is an impressive natural electromagnetic phenomenon occurring in atmosphere under suitable circumstances. Its origin, composition and stability issues are a matter of debate, due to presence of many evidences still…
The problem of a bouncing ball on a non-planar surface is investigated. We discovered that surface undulation adds a horizontal component to the impact force, which acquires a random character. Some aspects of Brownian motion are found in…
The coefficient of restitution $\epsilon$ characterizes the energy retained when a ball bounces, and can easily be measured in an ``at home'' experiment. For thin-walled gas-filled balls such as basketballs, we construct a simple two…
The dynamics is investigated of a free particle on a sphere (rigid rotor or rotator) that is initially in a coherent state. The instability of coherent states with respect to the free evolution leads to nontrivial time-development of…
Sound can complement vision in ball sports by providing subtle cues about contact dynamics. In table tennis, the brief, high-frequency sounds produced during racket-ball impacts carry information about the racket type, the surface…
A large linewidth of electronic transition of an electron trapped in a bubble ("bubblonium") possesses natural, or radiative, and inhomogeneous components. The latter mechanism of the line broadening requires dissipation. Dissipation of…
We give an explanation for the onset of wind-induced flutter in a flag. Our theory accounts for the various physical mechanisms at work: the finite length and the small but finite bending stiffness of the flag, the unsteadiness of the flow,…
When a drop impacts a deep pool, it forms a crater which subsequently rebounds. Under certain conditions, a dimple forms at the crater bottom, which pinches off to entrap a small bubble. The oscillation of this entrapped bubble is the…
Have you ever played or watched a game of pool? If so, you have already seen a billiard system in action. In mathematics and physics, a billiard system describes a ball that moves in straight lines and bounces off walls. Despite these…
We study the instabilities occurring during the burst of an air balloon in a liquid. These instabilities are typical for the deformation of an interface between two fluids of different densities, similar to fingering in Rayleigh-Taylor…