A teacher opens a window on a cold day. Which statement explains why the room starts to feel cooler?
1. The density of the air is lower on the inside than on the outside.
2. Air moves from the areas of higher temperature to areas of lower temperature.
3. Cold air is moving into the room from outside.
4. The kinetic energy of the air molecules outside is higher than the kinetic energy of the air molecules inside.
2. Air moves from the areas of higher temperature to areas of lower temperature.
The correct statement that explains why the room starts to feel cooler when a teacher opens a window on a cold day is:
2. Air moves from the areas of higher temperature to areas of lower temperature.
When the window is opened, the colder outside air with a lower temperature seeps into the room. Air tends to move from areas of higher temperature to areas of lower temperature in order to equalize the temperature. Therefore, the warmer air inside the room moves out, causing the room to feel cooler.
The correct statement that explains why the room starts to feel cooler when a teacher opens a window on a cold day is option 3: "Cold air is moving into the room from outside."
To understand why this is the correct explanation, we need to consider the concepts of temperature and heat transfer. When the window is opened, air from outside (which is typically colder on a cold day) enters the room. The air inside the room then comes into contact with the cold air from outside.
Heat transfer occurs due to the temperature difference between two objects or areas. In this case, the warmer air inside the room will transfer its heat energy to the colder air entering from outside. This leads to a decrease in the temperature of the air inside the room and consequently, the room starts to feel cooler.
Options 1 and 4 are not correct explanations. The density of the air (option 1) does not directly affect the sensation of temperature, and the kinetic energy of air molecules (option 4) relates more to the speed of the molecules rather than temperature.
Option 2 is not the best explanation in this scenario because while air does move from areas of higher temperature to areas of lower temperature, it doesn't fully explain why the room feels cooler. The movement of air is a result of the temperature difference, but the transfer of heat energy from the warmer air inside to the colder air entering the room is the primary reason for the room feeling cooler.