Question

Деталям из меди и железа подвели одинаковое количество теплоты и нагрели до одинаковой температуры. Нужно сравнить массу деталей меди с массой деталей железа, если удельная теплоёмкость у меди 400 Дж/кг*С°, а у железа 500 Дж/кг*С°?

Answer 1

Дано: Q1=Q2; Δt1=Δt2; см=400Дж/кг°С; сж=500 Дж/кг°С; mм/mж - ?
Q1=cм*mмΔt
Q1=cж*mжΔt
Q1/Q2=400*mм*Δt/500*mж*Δt

1=0,8*(mм/mж)*1

mм/mж=1/0,8=5/4 - значит масса меди 5 частей, масса железа 4 таких же части.
Меди больше нагрели, т.к. ее удел. теплоемкость меньше.

Answer 2

Дано:
∆t1 = ∆t2 = ∆t
Q1 = Q2
c1 = 400 Дж/кг°С
c2 = 500 Дж/кг°С
Найти: m1/m2 - ?
Решение:
Q1 = ∆tm1c1
Q2 = ∆tm2c2
∆tm1c1 = ∆tm2c2
m1c1 = m2c2
m1/m2 = c2/c1
m1/m2 = 500 Дж/кг°С/400 Дж/кг°С = 1,25
Ответ: масса детали из меди больше массы детали из железа в 1,25 раз.

Answer 3

Answer in detail. The details of copper and iron were given the same amount of heat and heated to the same temperature. You need to compare the mass of the copper parts with the mass of the iron parts, if the specific heat capacity of copper is 400 J / kg * C °, and of iron 500 J / kg * C °?

To answer this question, we need to use the formula for the amount of heat transferred to a body: $$Q = mc\Delta T$$, where $$Q$$ is the heat, $$m$$ is the mass, $$c$$ is the specific heat capacity, and $$\Delta T$$ is the change in temperature. Since the details of copper and iron were given the same amount of heat and heated to the same temperature, we can write the following equation: $$Q_{Cu} = Q_{Fe}$$, or $$m_{Cu}c_{Cu}\Delta T = m_{Fe}c_{Fe}\Delta T$$. We can rearrange this equation to find the ratio of the masses of the copper and iron parts: $$\frac{m_{Cu}}{m_{Fe}} = \frac{c_{Fe}}{c_{Cu}}$$. Substituting the given values of the specific heat capacities, we get: $$\frac{m_{Cu}}{m_{Fe}} = \frac{500}{400} = 1.25$$. This means that the mass of the copper parts is 1.25 times greater than the mass of the iron parts. For example, if the mass of the iron parts is 1 kg, then the mass of the copper parts is 1.25 kg.