Question

Пожалуйста помогите, решить задачу!!.Какую массу воды можно нагреть от 10 до 100 градусов Цельсия за счет энергии, получаемой за 15 мин электрическим чайником, включенным в сеть напряжением 220 В при силе тока 2 А?

Answer 1

Количество теплоты для нагревания воды равно: c(воды)*m(воды)*90(дельта температуры, сразу подставлю чтоб её за собой не тащить)

Есть такая формула, что Q=U*I*t   t-время. Приравниваем эти 2 уравнения, получаем:

 

c(воды)*m(воды)*90=U*I*t

 

решая это уравнение выражаешь лего m:

m=(U*I*t ):(90*c(воды)) Подставим значения:

m= (220*2*15*60)/(4200*90) 60 взялось т.к. мы решаем задачу в системных единицах- секунды

m=1 кг

ответ: m=1 кг

Answer 2

Calculation of the Mass of Water Heated

To calculate the mass of water that can be heated from 10 to 100 degrees Celsius using the energy obtained from an electric kettle, we need to consider the power of the kettle and the time it is connected to the power supply.

Given: - Voltage (V) = 220 V - Current (I) = 2 A - Time (t) = 15 minutes = 900 seconds - Initial temperature (T1) = 10 degrees Celsius - Final temperature (T2) = 100 degrees Celsius

To calculate the mass of water, we can use the formula:

Q = m * c * ΔT

Where: - Q is the heat energy transferred to the water - m is the mass of water - c is the specific heat capacity of water - ΔT is the change in temperature

The specific heat capacity of water is approximately 4.18 J/g°C.

To find the heat energy transferred to the water, we can use the formula:

Q = P * t

Where: - P is the power of the kettle - t is the time the kettle is connected to the power supply

The power (P) can be calculated using the formula:

P = V * I

Let's calculate the mass of water that can be heated using these formulas.

Calculation Steps:

1. Calculate the power (P) of the kettle: - P = V * I - P = 220 V * 2 A - P = 440 W

2. Calculate the heat energy transferred to the water (Q): - Q = P * t - Q = 440 W * 900 s - Q = 396,000 J

3. Calculate the change in temperature (ΔT): - ΔT = T2 - T1 - ΔT = 100°C - 10°C - ΔT = 90°C

4. Calculate the mass of water (m): - Q = m * c * ΔT - m = Q / (c * ΔT) - m = 396,000 J / (4.18 J/g°C * 90°C) - m ≈ 1125.89 g

Therefore, the mass of water that can be heated from 10 to 100 degrees Celsius using the energy obtained from the electric kettle, connected to the power supply for 15 minutes, is approximately 1125.89 grams.

Please note that this calculation assumes that all the energy from the kettle is transferred to the water and that there are no heat losses during the heating process.