which causes the thermal energy in a building to decrease?\nthe air conditioner and the heat engine\nthe…

which causes the thermal energy in a building to decrease?\nthe air conditioner and the heat engine\nthe furnace and the heat pump\nthe heat pump and the air conditioner\nthe heat engine and the furnace

which causes the thermal energy in a building to decrease?\nthe air conditioner and the heat engine\nthe furnace and the heat pump\nthe heat pump and the air conditioner\nthe heat engine and the furnace

Answer

Explanation:

Step1: Understand the function of each device

  • Air conditioner: Removes heat from the building (indoor space) and expels it outside, which reduces the thermal energy inside the building.
  • Heat engine: Converts thermal energy into mechanical work. It does not directly reduce the thermal energy of a building.
  • Furnace: Generates heat and increases the thermal energy of a building.
  • Heat pump: Can be used in cooling mode (similar to an air - conditioner in the sense of removing heat from a space). In cooling mode, it takes heat from the building (lower - temperature reservoir) and transfers it to the outside (higher - temperature reservoir), thus decreasing the thermal energy of the building.

Step2: Analyze each option

  • Option 1 (the air conditioner and the heat engine): The heat engine does not decrease the thermal energy of the building.
  • Option 2 (the furnace and the heat pump): The furnace increases the thermal energy of the building.
  • Option 3 (the heat pump and the air conditioner): Both can remove heat from the building (when the heat pump is in cooling mode), decreasing the thermal energy.
  • Option 4 (the heat engine and the furnace): The heat engine does not decrease the thermal energy and the furnace increases it.

Answer:

the heat pump and the air conditioner