Question

Помогите срочно,Очень нужно 1. Розрахуйте кількість теплоти, необхідну для нагрівання 5 кг олії на 45 °С. 2. Розрахуйте кількість теплоти, необхідну для нагрівання мідної ложки масою 30 г від 20 до 40 °С.

Answer 1

Ответ: 382500; 240Дж

Объяснение:

1) Для нагревания масла подсолнечного на 45°С необходимо следующее количество теплоты:

Q=c*m*Δt=1700*5*45=382500Дж

2) Для нагревания медной ложки необходимо следующее количество теплоты:

Q=c*m*Δt=400*0,03*(40-20)=400*0,03*20=240Дж

Answer 2

Calculation of heat required to heat 5 kg of oil from 25°C to 45°C:

To calculate the heat required to heat a substance, we can use the formula:

Q = m * c * ΔT

Where: - Q is the heat energy in Joules (J) - m is the mass of the substance in kilograms (kg) - c is the specific heat capacity of the substance in J/(kg·°C) - ΔT is the change in temperature in degrees Celsius (°C)

For oil, the specific heat capacity can vary depending on the type of oil. However, a commonly used value for the specific heat capacity of vegetable oil is approximately 2.0 J/(g·°C) or 2000 J/(kg·°C) [[1]].

Given: - Mass of oil (m) = 5 kg - Change in temperature (ΔT) = 45°C - 25°C = 20°C - Specific heat capacity of oil (c) = 2000 J/(kg·°C)

Using the formula, we can calculate the heat required (Q):

Q = 5 kg * 2000 J/(kg·°C) * 20°C = 200,000 J

Therefore, the heat required to heat 5 kg of oil from 25°C to 45°C is 200,000 Joules.

Calculation of heat required to heat a copper spoon weighing 30 g from 20°C to 40°C:

Similar to the previous calculation, we can use the formula:

Q = m * c * ΔT

Given: - Mass of copper spoon (m) = 30 g = 0.03 kg - Change in temperature (ΔT) = 40°C - 20°C = 20°C

The specific heat capacity of copper is approximately 385 J/(kg·°C) [[2]].

Using the formula, we can calculate the heat required (Q):

Q = 0.03 kg * 385 J/(kg·°C) * 20°C = 231 J

Therefore, the heat required to heat a copper spoon weighing 30 g from 20°C to 40°C is 231 Joules.

Please note that these calculations assume no heat loss to the surroundings and that the specific heat capacity values used are approximate averages.