В герметичному балоні об'ємом 165л, знаходиться кипляча вода масою 70 кг та пара при температурі в 100*С (повітря в балоні немає Вирахувати масу пари.

ЛЯ РЕШЕНИЯ ЗАДАЧ С ТОНКИМИ ЛИНЗАМИ НАДО

знать совсем немного. Напомним их основные свойства.

1) Характер линзы зависит от радиусов образующих ее

сферических поверхностей и от показателя преломления

материала линзы относительно окружающей среды

n n n = л ср . При n > 1 двояковыпуклая и плосковыпуклая

линзы – собирающие, двояковогнутая и плосковогнутая

линзы – рассеивающие; при n < 1 – наоборот. Эти утверждения следуют из формулы для фокусного расстояния F:

( )

1 2

1 1 1

n 1

F R R

Ê ˆ

= - + Á ˜ Ë ¯ ,

где радиус выпуклой поверхности считается положительным, а радиус вогнутой – отрицательным. Если F положительно, то линза собирающая, в противном случае – рассеивающая. Эту формулу знать полезно, но необязательно.

Пример 1

. Из очень тонких одинаковых сферических стеклянных сегментов изготовлены линзы, представленные на рисунке 1. Если показатель преломления глицерина больше, чем показатель преломления воды, то собирающая линза представлена на рисунке: 1); 2); 3); 4).

(ответ: 4).)

2) Для решения задач полезно знать ход основных лучей.

а) Лучи, идущие через оптический центр линзы, не испытывают отклонения.

б) Лучи, падающие параллельно главной оптической оси

(рис.2), сходятся в фокусе, лежащем за линзой – в случае

Объяснение:

60,2 Arnold Schwarzenegger (born 30.07.1947) - American actor, sportsman and politician.

While his police-chief father wanted him to become a soccer player, Austrian-born actor Arnold Schwarzenegger opted instead for a bodybuilding career. Born July 30, 1947, in the small Austrian town of Graz, Schwarzenegger went on to win several European contests and international titles (including Mr. Olympia) and then came to the U.S. for body-building exhibitions, billing himself immodestly but fairly accurately as "The Austrian Oak." Though his thick Austrian accent and slow speech patterns led some to believe that the Austrian Oak was shy a few leaves, Schwarzenegger was, in fact, a highly motivated and intelligent young man. After graduating from the University of Wisconsin with a degree in business and economics, he invested his contest earnings in real estate and a mail-order bodybuilding equipment company.

A millionaire before the age of 22, Schwarzenegger decided to try acting. Producers were impressed by his physique but not his mouthful of a last name, so it was as Arnold Strong that he made his film bow in the low-budget spoof Hercules in New York (1970) (with a dubbed voice). He reverted to his own name for the 1976 film Stay Hungry, then achieved stardom as "himself" in the 1977 documentary Pumping Iron. In The Villain (1979), a cartoon-like Western parody, he played "Handsome Stranger," exhibiting a gift for under-stated comedy that would more or less go unexploited for many years thereafter. With Conan the Barbarian (1982) and its sequel, Conan the Destroyer (1984), the actor established himself as an action star, though his acting was backtracking into two-dimensionality (understandably, given the nature of the Conan role). As the murderous android title character in The Terminator (1984), Schwarzenegger became a bona fide box-office draw, and also established his trademark of coining repeatable catch phrases in his films: "I'll be back," in Terminator, "Consider this a divorce," in Total Recall (1990), and so on.