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(GALILEI, Cited by: Thuillier, 1994, p. 120). ACTIVITY In a game of pool ball continues moving after the action ceased transmitted by the bat through the player's hand. Think of other everyday situations and reply: Why in some situations, even when the action ends movement of the force does not cease to exist or remain for a while? Reflect. Discuss with your colleagues. Remember the experience of the inclined plane? Galileo concludes that when there was no decrease (downward plane) or increase (upward plane) had no acceleration, ie the speed of the body remained constant. But in ourday-to-day, we realize that the body moves in a straight line just stopping. What makes the body stops its movement on a horizontal surface? What else should be taken into account? In describing the preparation necessary to carry out the experiment Galileo talks about polishing the surfaces. See what he says in the quote Thuillier (1994): "On a ruler, or more exactly a beam of wood, measuring about six feet long and the width of three fingers, dug a small canal with little more than a finger, perfectly straight, then the guarnecemos with a sheet of parchment and glossy, tomake it as slippery as possible, run over and left him a bronze ball pretty hard, perfectly round and polished " Actually what he realized is that the deslizarmos a body on a surface appears another force acting on that body is friction. And it is the friction that causes the body to stop and not the law that is incorrect. If there were no friction, the bodies in uniform rectilinear motion and remain eternally in this movement. But how to measure this resistance? The extent of this resistance is your body'smomentum. For Newton, this quantity, which he called the amount of movement is proportional to its velocity. The mass, whose property is to resist the change of state of motion, is the constant of proportionality between themomentum of the particle and its velocity. Thus we can write: Q = m. This quantity is constant when no net force acting on the body, that is, when the external force on the body is zero. Classical description of motion: inertia and momentum.41
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(Galilei, citiranja:. Thuillier, 1994, str 120). AKTIVNOST U igri bazen loptu nastavlja s radom nakon akcije prestala prenosi šišmiš kroz igračev ruci. Razmislite o drugim svakodnevnim situacijama i odgovorite: Zašto se u nekim situacijama, čak i kada je akcija završava kretanje snagu ne prestaje postojati ili ostati neko vrijeme? Razmišljajte. Razgovarajte sa svojim kolegama. Zapamti iskustvo u kosi zrakoplovom? Galileo zaključuje da, kada nije bilo smanjenje (u padu zrakoplova) ili povećanje (gore avion) imao ubrzanje, odnosno brzinu tijela ostala konstanta. No, u našemdana u dan, shvaćamo da je tijelo se kreće u ravnoj liniji samo zaustavljanje. Što čini tijelo sprečava njeno kretanje na horizontalnu površinu? Što još treba uzeti u obzir? U opisivanju pripreme potrebne za obavljanje pokusa, Galileo razgovore o poliranja površine. Pogledajte što on kaže u quote Thuillier (1994): "On je vladar, ili točnije širina od drveta, dimenzija oko šest metara dug i širine tri prsta, iskopao mali kanal s nešto više od prstiju, savršeno ravna, onda guarnecemos sa listom pergamenta i sjajnom, dabi ga kao sklizak što je više moguće, pregazio i ostavio mu je brončanu loptu prilično tvrdo, savršeno okrugla i sjajnog " Zapravo ono što je on shvatio je da deslizarmos tijelo na površini pojavi još jedna sila koja djeluje na to tijelo je trenje. I to je trenje koje uzrokuje da tijelo zaustavi, a ne zakon koji je netočna. Kad ne bi bilo trenja, tijela u odori pravocrtno gibanje i ostati vječno u tom pokretu. No, kako se mjeri taj otpor? Opseg ovog otpora je vaše tijelo jezamah. Za Newtona, ova količina, koju je nazvao iznos kretanja proporcionalna svojoj brzini. Masa, a imovina im je odoljeti promjenu stanja gibanja, je konstanta proporcionalnosti izmeđuzamah čestice i njegove brzine. Tako možemo pisati: Q = m. Ova količina je konstantna kada nema net sila koja djeluje na tijelo, odnosno, kada je vanjska sila na tijelo je nula. Klasični opis gibanja: tromost i41 zamah.