A researcher is cooling a metal. She cools the metal so that the temperature of the metal drops at a constant rate. After 11 minutes of cooling, the metal is 321 c. After 21 minutes, the metal is 131 c.
(a)Choose the statement that best describes how the time and the temperature of the metal are related. Then fill in the blank.
A) As time increases, the temperature of the metal decreases.
or
B) As time increases, the temperature of the metal increases.
(b)What was the temperature of the metal when the researcher started cooling it?
(a) The statement that best describes the relationship between time and temperature of the metal is A) As time increases, the temperature of the metal decreases.
(b) To find the temperature of the metal when the researcher started cooling it, we need to determine the rate at which the temperature is decreasing.
The time difference between 21 minutes and 11 minutes is 21 - 11 = 10 minutes.
The temperature difference between 131 degrees Celsius and 321 degrees Celsius is 131 - 321 = -190 degrees Celsius.
Therefore, the cooling rate is -190 degrees Celsius / 10 minutes = -19 degrees Celsius per minute.
To find the initial temperature when the researcher started cooling it, we can multiply the cooling rate by the number of minutes it takes for the temperature to decrease to zero, in this case, 11 minutes.
-19 degrees Celsius per minute * 11 minutes = -209 degrees Celsius.
Thus, the temperature of the metal when the researcher started cooling it was 209 degrees Celsius.