SearcharxivSearch

arXiv subjects

Fernanda Santana

Publications and source records attributed to Fernanda Santana.

2 recordsLinked to original sources

Tautochrone in the damped cycloidal pendulum

The tautochrone on a cycloid curve is usually considered without drag force. In this work, we investigate the motion of a damped cycloidal pendulum under presence of a drag force. Using the Lagrange formulation, and considering linear dependence with velocity for damping force, we found the dynamics of the system to remain tautochrone. This dictates the possibility for studying the tautochrone experimentally, e.g. the cycloidal pendulum in water or oil.

physics.class-ph

Estimation of solar illumination time on the earth by an analytical model: a fertile scenery for to teach physics

We proposed an analytical model for the calculus of illumination time of the Earth for any time of year and any latitude, this model assumes the obliquity of the ecliptic as constant, the light beams as parallels, the Earth as spherical, the movement of translation of Earth as uniform circular, also this model showed a context of the astronomy whereby the teachers can teach the basic physics.It was built through a relationship between the movement of translation and of rotation of the wave front light, then we found the of illumination zone on the Earth and the illumination time is estimated in a particular latitude with the uniform circular movement of Earth. Present model was confronted with the numerical results of the Geoscience Australia Agency and it is found a maxim perceptual error of 1,6%, this value was assigned primarily to the difference between the circular trajectory, in this model, and the elliptical trajectory that is the real. Without the use of spherical trigonometry was obtained an analytical model that estimates very close the solar illumination time at any time of year and any latitude on earth, the model provides an authentic context for studying basic aspects of physics.

astro-ph.EP