8-§. Termodinamika asoslari asosiy formulalar

Masalalar yechish namunalari


1- masala. Normal sharoitda 1kmol azot adiabatik V₁ hajmdan V₂=5V₁ hajmgacha kengayadi. 1) Gaz ichki energiyasining o‘zgarishi, 2) kengayishda bajarilgan ish topilsin.

Berilgan: ν = 1kmol = 1000 m V2=5V1 _______________________∆W=?,A=?

Yechish: ∆W=-A, i=5, , ∆W=-2.69 MJ, A=2.69MJ. Javob: ∆W=-2.69 MJ, A=2.69MJ ga teng.

2- masala.Ideal gazga 400 J issiqlik miqdori berilganda, gaz ezotermik kengayib qancha ish bajaradi?

Berilgan: Q=400J T = const ___________________ A=?

Yechish: T = const asosan: Q = ∆U + A ∆U = 0. Demak, Q= A A = Q = 400J Javob: A = 400J.

3- masala.Ballon ichidagi argon gaziga 40J issiqlik miqdori berilganda, uning temperaturasi 8 K ga oshdi. Gaz massasini toping (kg). Argonning molyar massasi 40 g/mol.

Berilgan: Q = 40J V = const ∆ T = 8 K __________________ m=?

Yechish: Termodinamikaning I qonuniga asosan Q = ∆U + A (1), V = const, A = P∆V (2) Demak, Javob: m = 16 ∙10^-3 kg.