Answer:
En 1589 Galileo realizó un experimento lanzando dos bolas de diferentes masas desde la famosa Torre Inclinada de Pisa para demostrar que el tiempo de caída es independiente de la masa de la bola. A través de este experimento, Galileo descubrió que los cuerpos caían casi simultáneamente, refutando la teoría de Aristóteles de que la tasa de caída era proporcional a la masa del cuerpo.
Debido a la imperfección de los equipo de medición de esa época, la caída libre de los cuerpos era casi imposible de estudiar. En busca de una forma de reducir la velocidad de movimiento, Galileo reemplazó la caída libre por rodar sobre una superficie inclinada, donde había velocidades y resistencia del aire significativamente más bajas. Se notó que con el tiempo, la velocidad del movimiento aumenta: los cuerpos se mueven con aceleración. Se concluyó que la velocidad y la aceleración no dependen ni de la masa ni del material de la pelota.
<span> An electroscope that might have a static charge is tested on a metal surface. From there, the charges move to the metal and straight to the foil leaves. If they repel, or move away from each other, that means they have identical charges. This applies for both positive and negative static electricity.
work cited: School of champions, Google
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The mechanical energy isn't conserved. Some energy is lost to friction.
Option A.
<h3><u>Explanation:</u></h3>
The mechanical energy is defined as the energy of a body which it achieves by virtue of its position and velocity. The mechanical energy are of two types - potential energy and kinetic energy. The potential energy is the energy of the body which it achieves by means of its relative position and is directly proportional to the height of the body from its relative plane. Whereas the kinetic energy of the body is achieved by virtue of its velocity and is directly proportional to the square of velocity of the body.
As the mountaineer is skiing down the slope of a mountain, the potential energy of the person is gradually changing into his kinetic energy. Had it been in an ideal situation, the potential energy lost would have been just equal to the kinetic energy gained by the person. But there's friction which opposes the speed of the body and reduces the velocity. Thus the kinetic energy will be lost to some extent and the energy won't be conserved.
It is a battery (the long and short lines represent 2 cells)