A researcher is cooling a metal. She cools the metal so that the temperature of the metal drops at a constant minutes of cooling, the metal is 390 °C. After 40 minutes, the metal is 110 °C.

Question

Choose the statement that best describes how the time and the temperature of the metal are related. Then fill in the blanks.
*
* As time increases, the temperature of the metal decreases.
The temperature of the metal decreases at a rate of ____ °C per minute.
*
* As time increases, the temperature of the metal increases.
The temperature of the metal increases at a rate of ____°C per minute.

What was the temperature of the metal when the researcher started cooling it? ___∘C

Answer 1

To find the rate at which the temperature of the metal decreases, we can calculate the change in temperature over the time period.

Initial temperature = 390 °C
Final temperature = 110 °C
Time period = 40 minutes

The change in temperature is: \[ \text{Change in temperature} = \text{Initial temperature} - \text{Final temperature} = 390 , °C - 110 , °C = 280 , °C \]

Now, we can calculate the rate of temperature decrease per minute: \[ \text{Rate of temperature decrease} = \frac{\text{Change in temperature}}{\text{Time period}} = \frac{280 , °C}{40 , \text{minutes}} = 7 , °C/\text{minute} \]

So, we can fill in the blanks in the statement:

• As time increases, the temperature of the metal decreases. The temperature of the metal decreases at a rate of 7 °C per minute.
• As time increases, the temperature of the metal increases. The temperature of the metal increases at a rate of N/A (since it is actually decreasing, this statement does not apply in this context).

The initial temperature of the metal when the researcher started cooling it was: 390 °C.

To summarize the answers:

• The temperature of the metal decreases at a rate of 7 °C per minute.
• The initial temperature of the metal was 390 °C.

Answer 2

There are 3 questions

* As time increases, the temperature of the metal decreases.
The temperature of the metal decreases at a rate of ____ °C per minute.
*
* As time increases, the temperature of the metal increases.
The temperature of the metal increases at a rate of ____°C per minute.

What was the temperature of the metal when the researcher started cooling it? ___∘C

Answer 3

Here are the answers to the three questions:

1. As time increases, the temperature of the metal decreases. The temperature of the metal decreases at a rate of 7 °C per minute.

2. As time increases, the temperature of the metal increases. The temperature of the metal increases at a rate of 0 °C per minute (since it is actually decreasing, this statement does not apply).

3. What was the temperature of the metal when the researcher started cooling it? 390 °C.

To summarize:

• Rate of temperature decrease: 7 °C per minute
• Rate of temperature increase: 0 °C per minute
• Initial temperature: 390 °C