HEAT TRANSFER + RADIATION

Assertion : Radiation is the speediest mode of heat transfer. Reason : Radiation can be transmitted in zig-zag motion.

Look at Figure. Mark where the heat is being transferred by conduction, by convection and by radiation.

Heat Transfer Basic Idea|| Conduction

Heat Transfer Basic Idea|| Conduction

Assertion: CO_(2) present in the atmosphere absorbs heat radiated from heat radiated from earth in the form of IR radiations. Reason: CO_(2) is a pollutant.

Assertion : Bodies radiate heat at all temperatures. Reason : Rate of radiation of heat is proportional to the fourth power of absolute temperature.

Define radiation. Give any two examples where heat is transferred by radiation. What is the name of invisible heat rays which transfer heat by radiation ?