Вычислить изменение внутренней энергии одного моля идеального одноатомного газа, а также количество тепла, поглощенного при расширении газа по политропы pV ^ 3 = const от объема V1 = 1л и давления p1 = 2МПа к объему V2 = 3л.
the person i admire most in the world is nelson mandela. he was the president of south arm.he was put in prison because of his political beliefs. he wanted to get equal rights for black people in south africa.he was a lawyer before he went to prison and he represented himself at his trial.the reason that i admire him is that in spite of the fact that he spent such a long time in prison he never changed his views.
i think he's really influenced the way people think about how they can make changes, political changes, by standing by what they believe in and stating their beliefs very clearly.
остальное я думаю можно выкинуть-смысл и так сохраняется) кстати мне тоже нравится этот политик, ведь он как никак выступал за права людей, ведь чернокожие люди такими же правами как и мы с вами : )
R1 = R2 = 10 Ом.
U = 220 В.
m1 = 1 кг.
m2 = 300 г = 0,3 кг.
T = 37 с.
t2 = 100 °С.
С1 = 4200 Дж/кг *°С.
С2 = 900 Дж/кг *°С.
t1 - ?
При параллельном соединение спиралей общее их сопротивление R найдём по формуле: R = R1 *R2/(R1 + R2).
R = 10 Ом *10 Ом/(10 Ом + 10 Ом) = 5 Ом.
Согласно закону Джоуля-Ленца, в плитке выделяется количество теплоты Q = U2 *T/R.
Это количество теплоты Q идёт на нагревание воды от t1 до температуры кипения t2.
Q = C1 *m1 *(t2 - t1) + C2 *m2 *(t2 - t1) = C1 *m1 *t2 - C1 *m1 *t1 + C2 *m2 *t2 - C2 *m2 *t1.
U2 *T/R = C1 *m1 *t2 - C1 *m1 *t1 + C2 *m2 *t2 - C2 *m2 *t1.
C1 *m1 *t1 + C2 *m2 *t1 = C1 *m1 *t2 + C2 *m2 *t2 - U2 *T/R.
t1 = (C1 *m1 *t2 + C2 *m2 *t2 - U2 *T/R) /(C1 *m1 + C2 *m2).
t1 = (4200 Дж/кг *°С *1 кг *100 °С+ 900 Дж/кг *°С *0,3 кг *100 °С - (220 В)2 *37 с/5 Ом) /(4200 Дж/кг *°С *1 кг + 900 Дж/кг *°С *0,3 кг) = 19,8 °С.
ответ: начальная температура воды составляла t1 = 19,8 °С.
Объяснение:
the person i admire most in the world is nelson mandela. he was the president of south arm.he was put in prison because of his political beliefs. he wanted to get equal rights for black people in south africa.he was a lawyer before he went to prison and he represented himself at his trial.the reason that i admire him is that in spite of the fact that he spent such a long time in prison he never changed his views.
i think he's really influenced the way people think about how they can make changes, political changes, by standing by what they believe in and stating their beliefs very clearly.
остальное я думаю можно выкинуть-смысл и так сохраняется) кстати мне тоже нравится этот политик, ведь он как никак выступал за права людей, ведь чернокожие люди такими же правами как и мы с вами : )