Răspuns :
Ce ne zice problema de fapt se poate scrie asa:
[tex]\dfrac{V_f}{V_i}=1,20\\ \\ \\ \dfrac{p_f}{p_i}=1,30\\ \\ \\ T_f-T_i=12[/tex]
Daca scriem ecuatia de stare in situatia finala si initiala, si apoi facem raportul lor, obtinem:
[tex]p_fV_f=\nu RT_f\\ p_iV_i=\nu RT_i\\ \\ \\ \dfrac{p_f}{p_i}\dfrac{V_f}{V_i}=\dfrac{T_f}{T_i}\\ \\ \\ T_f=\dfrac{p_f}{p_i}\dfrac{V_f}{V_i}T_i[/tex]
Acum inlocuim in ecuatia de mai sus cu diferenta de temperatura:
[tex]\dfrac{p_f}{p_i}\dfrac{V_f}{V_i}T_i-T_i=12\\ \\ \\ \left(\dfrac{p_f}{p_i}\dfrac{V_f}{V_i}-1\right)T_i=12[/tex]
Dupa ce faci niste calcule, gasesti usor T_i .
[tex]\dfrac{V_f}{V_i}=1,20\\ \\ \\ \dfrac{p_f}{p_i}=1,30\\ \\ \\ T_f-T_i=12[/tex]
Daca scriem ecuatia de stare in situatia finala si initiala, si apoi facem raportul lor, obtinem:
[tex]p_fV_f=\nu RT_f\\ p_iV_i=\nu RT_i\\ \\ \\ \dfrac{p_f}{p_i}\dfrac{V_f}{V_i}=\dfrac{T_f}{T_i}\\ \\ \\ T_f=\dfrac{p_f}{p_i}\dfrac{V_f}{V_i}T_i[/tex]
Acum inlocuim in ecuatia de mai sus cu diferenta de temperatura:
[tex]\dfrac{p_f}{p_i}\dfrac{V_f}{V_i}T_i-T_i=12\\ \\ \\ \left(\dfrac{p_f}{p_i}\dfrac{V_f}{V_i}-1\right)T_i=12[/tex]
Dupa ce faci niste calcule, gasesti usor T_i .