Q1: All modes of heat transfer i.e., conduction, convection & radiation occur in case of the

ANS:B - boiler furnace.

All modes of heat transfer, including conduction, convection, and radiation, occur in the boiler furnace. Explanation:

1. Conduction: Heat is transferred through solid materials by conduction. In a boiler furnace, heat is conducted through the walls of the furnace, transferring thermal energy to the water or steam inside.
2. Convection: Heat is transferred through fluid motion by convection. In a boiler furnace, hot gases generated by combustion rise due to their lower density, transferring heat to surrounding surfaces and contributing to the overall heat transfer process.
3. Radiation: Heat is transferred through electromagnetic waves by radiation. In a boiler furnace, combustion processes generate high temperatures, causing the furnace walls to emit thermal radiation. This radiation contributes to heating surfaces within the furnace and enhances heat transfer.

While condensation of steam in a partial condenser and steam-carrying insulated pipes involve heat transfer processes, they may not necessarily involve all three modes of heat transfer simultaneously. However, in a boiler furnace, where combustion occurs and high temperatures are present, all three modes of heat transfer are indeed involved in the heat exchange process. Therefore, the correct option is boiler furnace.