Question

1. it is 60° f inside petes house. the outside temperature is 40° f. pete turns on the central heat in the house to keep it warm. the heat is transferred throughout the house using .
2. allen mixes 1 cup of water that is 150° f and 1 cup of cold chicken broth that is 50° f. the end temperature of the mixture would be about .
3. bella combines 1 cup of coffee that is 150° f and a half cup of creamer that is 50° f . the

100 °f warm to cold less than 10 °f cold to warm
200 °f convection conduction
more than 200 °f more than 100 °f

Explanation:

Question 2

Step1: Recall heat transfer methods

Central heat systems (like forced - air systems) transfer heat through convection. Conduction is direct contact transfer, radiation is electromagnetic waves. Central heat uses air movement (convection) to distribute heat.

Step2: Match with options

Among the options, "convection" is the heat transfer method used in central heating for distributing heat in the house.

Step1: Use heat mixing concept

When mixing equal volumes (1 cup each) of two substances, the final temperature is approximately the average of the two initial temperatures. The formula for average (for equal masses/volumes, assuming same specific heat) is $\frac{T_1 + T_2}{2}$. Here, $T_1 = 150^{\circ}F$, $T_2=50^{\circ}F$.

Step2: Calculate the average

$\frac{150 + 50}{2}=\frac{200}{2}=100^{\circ}F$.

Step1: Recall heat mixing with different volumes

We have 1 cup of coffee at $150^{\circ}F$ and 0.5 cup of creamer at $50^{\circ}F$. Let's use the formula for heat mixing: $m_1c(T_1 - T_f)=m_2c(T_f - T_2)$ (assuming same specific heat $c$). Let $m_1 = 1$, $m_2 = 0.5$, $T_1 = 150$, $T_2 = 50$.
So, $1\times(150 - T_f)=0.5\times(T_f - 50)$

Step2: Solve the equation

$150 - T_f = 0.5T_f-25$
$150 + 25=0.5T_f+T_f$
$175 = 1.5T_f$
$T_f=\frac{175}{1.5}\approx116.67^{\circ}F$, which is more than $100^{\circ}F$.

Answer:

convection

Question 3