Т.к. p - константа, значит это изобарный процесс
V2/V1=T2/T1
V=m/p(плотность)
m2p/m1p=T2/T1
m2/m1=T2/T1
m2/0.09=450/300
300m2=40.5
m2=0.135кг
Вычтем из m2 m1, получим 0.045кг
N=U^2/R= 1210 Вт
A=Q1+Q2= (cm(100-15)+mL)* 0.8=( 4200*1.5*85+ 1.5* 2.25*10^6)=
535500+3375000=3910500
t=A/N= 3910500/1210=3231 секунда=0.9 часа
1)
![I=3A;\\ R_1=2 Om; \ R_2=3 Om\ R_3=5\ Om\\ R_{\sum}=R_1+R_2+R_3=(2+3+5)Om=10Om;\\ U=I\cdot R_{\sum}=I\cdot(R_1+R_2+R_3)=I\cdot R_1+I\cdot R_2+I\cdot R_3=\\ =U_1+U_2+U_3;\\\\ U_1=I\cdot R_1=3\cdot2=6 V;\\ U_2=I\cdot R_2=3\cdot3=9V;\\ U_3=I\cdot R_3=3\cdot5=15 V;\\ U=U_1+U_2+U_3=6+9+15=30 V;\\ U=I\cdot R_{\sum}=3\cdot10=30 V ](https://tex.z-dn.net/?f=I%3D3A%3B%5C%5C%0AR_1%3D2+Om%3B+%5C+R_2%3D3+Om%5C+R_3%3D5%5C+Om%5C%5C%0AR_%7B%5Csum%7D%3DR_1%2BR_2%2BR_3%3D%282%2B3%2B5%29Om%3D10Om%3B%5C%5C%0AU%3DI%5Ccdot+R_%7B%5Csum%7D%3DI%5Ccdot%28R_1%2BR_2%2BR_3%29%3DI%5Ccdot+R_1%2BI%5Ccdot+R_2%2BI%5Ccdot+R_3%3D%5C%5C%0A%3DU_1%2BU_2%2BU_3%3B%5C%5C%5C%5C%0AU_1%3DI%5Ccdot+R_1%3D3%5Ccdot2%3D6+V%3B%5C%5C%0AU_2%3DI%5Ccdot+R_2%3D3%5Ccdot3%3D9V%3B%5C%5C%0AU_3%3DI%5Ccdot+R_3%3D3%5Ccdot5%3D15+V%3B%5C%5C%0AU%3DU_1%2BU_2%2BU_3%3D6%2B9%2B15%3D30+V%3B%5C%5C%0AU%3DI%5Ccdot+R_%7B%5Csum%7D%3D3%5Ccdot10%3D30+V%0A%0A)
имеем общеее сопротивление 10 Ом
сопротивление на первом участке 2 Ом, на втором 3 Ом, на третьем 5 Ом
напряжение на первом 6 Вольт, на втором 9 Вольт, на третьем 15 Вольт, общее напряжение 30 Вольт
2)
![R_1=18 Om;\\ R_2=32 Om;\\ R_3=26 Om;\\ U=48V;\\ I_1=\frac{U}{R_1}=\frac{48}{18}=\frac{8}{3}A=2\frac23A;\\ I_2=\frac{U}{R_2}=\frac{48}{32}=\frac{3}{2}A=1\frac12A;\\ I_1=\frac{U}{R_3}=\frac{48}{26}=\frac{2}{1}A=2A;\\ I=I_1+I_2+I_3=\frac83+\frac32+2=\frac{8\cdot2+3\cdot3+2\cdot2\cdot3}{3\cdot2}=\\ =\frac{16+9+12}{6}=\frac{37}{6}=6\frac16A;\\ \frac{1}{R}=\frac1{R_1}+\frac1{R_2}+\frac1{R_3};\\ ](https://tex.z-dn.net/?f=R_1%3D18+Om%3B%5C%5C%0AR_2%3D32+Om%3B%5C%5C%0AR_3%3D26+Om%3B%5C%5C%0AU%3D48V%3B%5C%5C%0AI_1%3D%5Cfrac%7BU%7D%7BR_1%7D%3D%5Cfrac%7B48%7D%7B18%7D%3D%5Cfrac%7B8%7D%7B3%7DA%3D2%5Cfrac23A%3B%5C%5C%0AI_2%3D%5Cfrac%7BU%7D%7BR_2%7D%3D%5Cfrac%7B48%7D%7B32%7D%3D%5Cfrac%7B3%7D%7B2%7DA%3D1%5Cfrac12A%3B%5C%5C%0AI_1%3D%5Cfrac%7BU%7D%7BR_3%7D%3D%5Cfrac%7B48%7D%7B26%7D%3D%5Cfrac%7B2%7D%7B1%7DA%3D2A%3B%5C%5C%0AI%3DI_1%2BI_2%2BI_3%3D%5Cfrac83%2B%5Cfrac32%2B2%3D%5Cfrac%7B8%5Ccdot2%2B3%5Ccdot3%2B2%5Ccdot2%5Ccdot3%7D%7B3%5Ccdot2%7D%3D%5C%5C%0A%3D%5Cfrac%7B16%2B9%2B12%7D%7B6%7D%3D%5Cfrac%7B37%7D%7B6%7D%3D6%5Cfrac16A%3B%5C%5C%0A%5Cfrac%7B1%7D%7BR%7D%3D%5Cfrac1%7BR_1%7D%2B%5Cfrac1%7BR_2%7D%2B%5Cfrac1%7BR_3%7D%3B%5C%5C%0A)
![\frac1R=\frac{R_1\cdot R_2+R_1\cdot R_3+R_2\cdot R_3}{R_1\cdot R_2\cdot R_3}\\ \\ R=\frac{R_1\cdot R_2\cdot R_3}{R_1\cdot R_2+R_1\cdot R_3+R_2\cdot R_3}=\\ =\frac{18\cdot32\cdot26}{18\cdot32+18\cdot26+32\cdot26}=\\ =\frac{2\cdot9\cdot2\cdot13\cdot32}{2\cdot9\cdot2\cdot16+2\cdot9\cdot2\cdot13+2\cdot13\cdot2\cdot16}=\frac{32\cdot9\cdot13}{9\cdot16+9\cdot13+13\cdot16}=\frac{3744}{469}=7\frac{461}{469};\\ I=\frac{U}{R}=\frac{48\cdot469}{3744}=\frac{3\cdot469}{234}=\frac{469}{78}=7\frac{1}{78}](https://tex.z-dn.net/?f=%5Cfrac1R%3D%5Cfrac%7BR_1%5Ccdot+R_2%2BR_1%5Ccdot+R_3%2BR_2%5Ccdot+R_3%7D%7BR_1%5Ccdot+R_2%5Ccdot+R_3%7D%5C%5C+%0A+%5C%5C%0A+R%3D%5Cfrac%7BR_1%5Ccdot+R_2%5Ccdot+R_3%7D%7BR_1%5Ccdot+R_2%2BR_1%5Ccdot+R_3%2BR_2%5Ccdot+R_3%7D%3D%5C%5C%0A+%3D%5Cfrac%7B18%5Ccdot32%5Ccdot26%7D%7B18%5Ccdot32%2B18%5Ccdot26%2B32%5Ccdot26%7D%3D%5C%5C%0A+%3D%5Cfrac%7B2%5Ccdot9%5Ccdot2%5Ccdot13%5Ccdot32%7D%7B2%5Ccdot9%5Ccdot2%5Ccdot16%2B2%5Ccdot9%5Ccdot2%5Ccdot13%2B2%5Ccdot13%5Ccdot2%5Ccdot16%7D%3D%5Cfrac%7B32%5Ccdot9%5Ccdot13%7D%7B9%5Ccdot16%2B9%5Ccdot13%2B13%5Ccdot16%7D%3D%5Cfrac%7B3744%7D%7B469%7D%3D7%5Cfrac%7B461%7D%7B469%7D%3B%5C%5C+I%3D%5Cfrac%7BU%7D%7BR%7D%3D%5Cfrac%7B48%5Ccdot469%7D%7B3744%7D%3D%5Cfrac%7B3%5Ccdot469%7D%7B234%7D%3D%5Cfrac%7B469%7D%7B78%7D%3D7%5Cfrac%7B1%7D%7B78%7D+)