Дано: P = 500 Вт, V = 4литра = 0,004 м^3, t(1) = 15 °С, t(2) = 85 °C, t = 50мин = 3000с.
Найти: η - ?
P*η = A / t
η = A / t*P
η = cm ( t(2)-t(1) ) / t*P
η = c *(ρ*V) ( t(2)-t(1) ) / t*P
η = 4200 *(1000*0,004) ( 70 ) / 3000*500 = 0,784 ≈ 78%
Дано: P = 500 Вт, V = 4литра = 0,004 м^3, t(1) = 15 °С, t(2) = 85 °C, t = 50мин = 3000с.
Найти: η - ?
P*η = A / t
η = A / t*P
η = cm ( t(2)-t(1) ) / t*P
η = c *(ρ*V) ( t(2)-t(1) ) / t*P
η = 4200 *(1000*0,004) ( 70 ) / 3000*500 = 0,784 ≈ 78%