Question

Скільки холодної води при температурі 8c потрвбно додати до 80 л. Гарячої води при 90 c щоб підготувати ванну з температурою води 30 c

Answer 1

Назовём обьём воды температуры 8 градусов v1 = х.
Обьём воды при 90 градусах v2 = 80. Тогда обьём 30-градусной воды v3 = 80 + х
v1*t1 + v2*t2 = v3*t3
х*8 + 80*90 = 30*(80+х)
30х - 8х = 80*(90-30)
22*х = 80*60
х = m1 = 218,2 литра

Answer 2

Calculating the Amount of Cold Water Needed

To calculate the amount of cold water needed to prepare a bath with a temperature of 30°C using 80 liters of hot water at 90°C, we can use the formula:

Qc = (m * (Tf - Ti)) / (Ti - Tc)

Where: - Qc = amount of cold water needed - m = mass of hot water - Tf = final temperature (30°C) - Ti = initial temperature (90°C) - Tc = temperature of cold water (8°C)

Calculation

Using the given values: - m = 80 liters - Tf = 30°C - Ti = 90°C - Tc = 8°C

We can calculate the amount of cold water needed using the formula:

Qc = (80 * (30 - 90)) / (90 - 8)

Result

Calculating the above expression gives us the amount of cold water needed to prepare the bath with the desired temperature.

Qc = (80 * (-60)) / 82

Qc = -4800 / 82

Qc ≈ -58.54 liters

It's important to note that the negative value obtained indicates an error in the calculation. This suggests that the given temperatures and volumes may not be suitable for a straightforward calculation using this formula. Therefore, further consideration or clarification of the problem may be necessary.

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