Final answer:
Without specific information about the oil's cooling properties or a given formula for this specific situation, we cannot accurately calculate the time taken for the oil to cool from 50 degrees Celsius to 40 degrees Celsius.
Step-by-step explanation:
To determine the time it takes for the oil to cool from 50 degrees Celsius to 40 degrees Celsius, given that it originally cooled from 60 degrees Celsius to 50 degrees Celsius in 6 minutes, we should consider Newton's Law of Cooling. This law states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature. However, without specific information about the cooling properties of the oil (such as its specific heat capacity or the heat transfer coefficient), a direct calculation isn't possible to provide.
Due to the lack of information, we cannot assume a linear relationship between time and cooling because as the oil approaches the ambient temperature, the rate at which it cools down decreases. Therefore, without additional data or a given formula that describes the cooling process for this specific situation, we cannot accurately calculate the time it will take for the oil to cool from 50 degrees Celsius to 40 degrees Celsius.
In other words, the answer would require additional experimental data or a given empirical relation which is not provided in the question, thus preventing a calculation based on the information supplied.