1-By opening the door of a refrigerator ehich is inside a room, the temperature of the room :

A) decreases
B) increases
C) remains unchanged
D) first decreases and then increases******(my ans)

2- The thermometer used to measure very low temperature is -
A). Mercury thermometer
B). Alcohol thermometer
C). Pyrometer
D). Magnetic thermometer****(my ans)

Someone please check this!!!

I agree with both answers.

Thank you very much DrBob222

Yes right

To answer these questions, let's break them down and explain the concepts involved.

1. By opening the door of a refrigerator which is inside a room, the temperature of the room:
To understand this, we need to consider how a refrigerator works. Refrigerators use a cooling mechanism to remove heat from the inside and release it outside. When you open the door of a refrigerator, you are allowing warm air from the room to enter the refrigerator, and the refrigerator works harder to remove the heat from inside.

Therefore, the answer is D) first decreases and then increases.
Explanation: Initially, when you open the door, the warm air from the room enters the refrigerator, causing the temperature inside the refrigerator to increase. However, the refrigerator's cooling mechanism kicks in to remove the heat, thus decreasing the temperature inside the refrigerator. The heat removed from the refrigerator is then released into the room, causing the temperature of the room to increase.

2. The thermometer used to measure very low temperature is:
To measure very low temperatures accurately, common liquid-filled thermometers like mercury or alcohol thermometers might not be suitable. These thermometers have limitations in measuring extremely low temperatures due to the freezing points of the liquids they contain.

Instead, specialized thermometers like the pyrometer or magnetic thermometer are used to measure very low temperatures.

Therefore, the answer is C) Pyrometer.
Explanation: A pyrometer is a device that measures high temperatures, but it can also be used to measure very low temperatures by employing specialized techniques. It uses principles different from those of liquid-filled thermometers, allowing it to accurately measure extremely low temperatures.

While a magnetic thermometer does exist, it is not typically used to measure very low temperatures. It is more commonly used in scientific research or industrial applications where other types of thermometers might not be feasible.

Remember, these explanations are based on general scientific knowledge, but specific scenarios may have unique considerations. It's always good to consult relevant sources or experts for precise answers in specific situations.