5 research outputs found
Unconventional physical way for the orbital velocity evaluation
The trajectory and the orbital velocity are determined for an object moving in a gravitational system, in terms of fundamental and independent variables. In particular, considering a path on equipotential line, the elliptical orbit is naturally traced, verifying evidently the keplerian laws. The case of the planets of the solar system is presented
Measurement of the thermal expansion coefficient of an Al-Mg alloy at ultra-low temperatures
We describe a result coming from an experiment based on an Al-Mg alloy (~ 5%
Mg) suspended bar hit by an electron beam and operated above and below the
termperature of transition from superconducting to normal state of the
material. The amplitude of the bar first longitudinal mode of oscillation,
excited by the beam interacting with the bulk, and the energy deposited by the
beam in the bar are the quantities measured by the experiment. These
quantities, inserted in the equations describing the mechanism of the mode
excitation and complemented by an independent measurement of the specific heat,
allow us to determine the linear expansion coefficient of the material.Comment: 13 pages, 4 figure