Предмет: Физика, автор: assies

Сколько спирта надо сжечь , чтоб увеличить температуру воды массой 4кг , взятой при температуре 14°С до температуры 50°С

Ответы

Автор ответа: kirills1

2

m = $\frac{Q}{q}$

Q - кол-во теплоты
q - удельная теплота сгорания ( для спирта 30000000 Дж / кг )

Q = cmΔt

c - удельная теплоёмкость ( для воды 4200 Дж / кг * С )
m - масса ( 4 кг )
Δt - разности температур ( 50 С - 14 С = 36 С )

Q = 4200 * 4 * 36 = 604800 Дж

m = $\frac{604800}{30000000}$ = 0,02016 кг = 20,16 г

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