Question

Определи, на сколько градусов нагреется кусок чугуна, если он упадёт с высоты 35 м на землю. Считай, что вся кинетическая энергия чугуна переходит во внутреннюю энергию. Удельная теплоёмкость чугуна равна 550 Дж/(кг·°С). При расчётах прими g = 9,8 Н/кг. Ответ (округли до целых): пожалуйста помогите

Answer 1

Ответ:

вооооот

все жду лайка .... иди в школу

Answer 2

Calculation of the Temperature Increase of a Piece of Cast Iron

To calculate the temperature increase of a piece of cast iron when it falls from a height of 35 m to the ground, we need to consider the conversion of its kinetic energy into internal energy. The specific heat capacity of cast iron is given as 550 J/(kg·°C), and we will assume the acceleration due to gravity (g) to be 9.8 N/kg.

To begin, we need to calculate the initial kinetic energy (KE) of the cast iron using the formula:

KE = (1/2) * m * v^2

Where: - KE is the kinetic energy - m is the mass of the cast iron - v is the velocity of the cast iron just before impact

Since we are not given the mass of the cast iron, we cannot calculate the exact temperature increase. However, we can still provide a general approach to solving the problem.

Let's assume the mass of the cast iron is 1 kg for simplicity. We can calculate the initial velocity (v) using the formula:

v = sqrt(2 * g * h)

Where: - g is the acceleration due to gravity (9.8 N/kg) - h is the height from which the cast iron falls (35 m)

Substituting the given values, we find:

v = sqrt(2 * 9.8 * 35) ≈ 26.7 m/s

Now, we can calculate the initial kinetic energy (KE):

KE = (1/2) * m * v^2 = (1/2) * 1 * (26.7)^2 ≈ 357 J

Since we are assuming that all the kinetic energy is converted into internal energy, we can equate the initial kinetic energy to the change in internal energy (ΔU):

ΔU = KE = 357 J

Next, we can use the equation for the change in internal energy (ΔU) to calculate the temperature increase (ΔT) of the cast iron:

ΔU = m * c * ΔT

Where: - ΔU is the change in internal energy - m is the mass of the cast iron - c is the specific heat capacity of cast iron (550 J/(kg·°C)) - ΔT is the change in temperature

Rearranging the equation, we find:

ΔT = ΔU / (m * c)

Substituting the values, we have:

ΔT = 357 J / (1 kg * 550 J/(kg·°C)) ≈ 0.65 °C

Therefore, if the cast iron piece has a mass of 1 kg, it will increase in temperature by approximately 0.65 °C when it falls from a height of 35 m to the ground.

Please note that this calculation assumes that all the kinetic energy is converted into internal energy and that the mass of the cast iron is 1 kg. The actual temperature increase may vary depending on the mass and other factors.