Physics FC

Heat is transferred through 3 processes. What are they?

1-Conduction 2-Convection 3-Radiation

When standing barefoot on a floor, body heat is transferred into the floor based on the thermal conductivity k of the flooring material. The heat flow rate per unit area H is defined by: H=kΔT/L where ΔT is the difference in temperature over a distance L. The tiled part of a floor in a room at room temperature feels colder than the carpeted part because: A. the temperature of the tile is lower than the temperature of the carpet. B. the thermal conductivity of the tile is higher than the thermal conductivity of the carpet. C. the thermal conductivity of the tile is lower than the thermal conductivity of the carpet. D. heat travels a greater distance through the carpet.

Ans=B So, the thermal conductivity is what allows us to feel heat. If you don't have a high thermal energy, we can't feel the heat coming from you, regardless if it's colder than us or warmer. So, tile has a higher thermal conductivity than carpet. -Using the formula, we can assume L is the same, and that T is different (it's larger for tile than carpet) BUT you have to understand that Tile's H has to be bigger than Carpet's H (since you getting more thermal energy from tile than carpet)

If a liquid is at its exact boiling point, what will happen to the liquid when a small amount of heat is added to it? A. None of the liquid will turn to gas, and the temperature will increase. B. All the liquid will turn to gas, and the temperature will remain the same. C. A small amount of the liquid will turn to gas, and the temperature will increase. D. A small amount of the liquid will turn to gas, and the temperature will remain the same.

Ans=D

During a phase change, the temperature of the material A-Increases B-Decreases C-Stays the same

During a phase change, the temperature of the material remains constant even though heat is added or removed

What does conduction cause?

In conduction, intermolecular collisions cause heat to move between high- and low-temperature regions.

Conduction deals with intra/inter molecular collisions?

Intermolecular collisions

Molecules within __________ _________ ________ tend to move ______and therefore have ________kinetic energies

Molecules within high-temperature regions tend to move faster and therefore have larger kinetic energies

During a phase change from liquid to gas, does adding a little bit of heat increase the temperature?

NO IT DOES NOT YOU NEED A LOT OF HEAT TO A-Increase temp B-Change all the liquid matter into gas