Question

Электрический кипятильник со спиралью чопротивлением 160 Ом поместили в сосуд, содержащий воду массой 500г, и включили в сеть напряжением 220 В. Определите , на сколько градусов нагрелась вода за пять минут. Удельная теплоемкость воды равна 4200 Дж/(кг*градус Цельсия )Если можно обьяснитне по понятней.

Answer 1

P=A/t

A=IUt=U^/Rt работа виполняемая Электрическим кипятильником

P=U^2/R  мощность електрического кипятильника

A=Q=cmT работа которая идет на нагревания

P=cmT/t

приравниваем мощности

cmT/t=U^2/R

m=0.5 кг

 t=300 c

 T=(U^2*t)/(cmR)

 T=43

 

думаю это правильно))

 

Answer 2

Calculation of Heat Transfer

To determine the temperature increase of the water after five minutes of heating with an electric kettle, we need to calculate the amount of heat transferred to the water.

The formula for calculating the heat transfer is:

Q = m * c * ΔT

Where: - Q is the heat transferred (in joules) - m is the mass of the water (in kilograms) - c is the specific heat capacity of water (in joules per kilogram per degree Celsius) - ΔT is the change in temperature of the water (in degrees Celsius)

Given information: - Mass of water (m) = 500 grams = 0.5 kilograms - Specific heat capacity of water (c) = 4200 joules per kilogram per degree Celsius - Change in time (t) = 5 minutes

To calculate the change in temperature (ΔT), we need to find the heat transferred (Q) first.

Calculation of Heat Transferred (Q)

The formula for calculating the heat transferred is:

Q = P * t

Where: - Q is the heat transferred (in joules) - P is the power of the electric kettle (in watts) - t is the time (in seconds)

Given information: - Power of the electric kettle (P) = Voltage (V) / Resistance (R) - Voltage (V) = 220 volts - Resistance (R) = 160 ohms - Time (t) = 5 minutes = 300 seconds

Let's calculate the power of the electric kettle:

P = V / R

P = 220 / 160

P ≈ 1.375 watts

Now, let's calculate the heat transferred (Q):

Q = P * t

Q = 1.375 * 300

Q ≈ 412.5 joules

Calculation of Change in Temperature (ΔT)

Now that we have the heat transferred (Q), we can calculate the change in temperature (ΔT) using the formula:

Q = m * c * ΔT

Substituting the known values:

412.5 = 0.5 * 4200 * ΔT

Simplifying the equation:

ΔT = 412.5 / (0.5 * 4200)

ΔT ≈ 0.049 °C

Therefore, the water will heat up by approximately 0.049 degrees Celsius after five minutes of heating with the electric kettle.

Please note that this calculation assumes no heat loss to the surroundings and that the specific heat capacity of water remains constant over the temperature range.