Question

Transmission of heat by molecular collision is called

1. Convection
2. Conduction
3. Radiation
4. Ionisation

Answer 1

Correct Answer - Option 2 : Conduction

​CONCEPT:

Three modes of Transmission of heat/heat flow
Sr. No	Conduction	Convection	Radiation
1	Heat dissipates from one place to another by molecular vibration or collision	Heat is transfer from one place to another by transfer of molecules	It transfers heat in the form of electromagnetic wave
2	Conduction is relevant to solid only.	Convection happens in liquid or gases	It can heat any form of material.
3	Need medium to transfer heat	Need medium to transfer heat	No need of medium
4	Good Conductor- The objects which transfer heat easily. Ex- metals, human body etc Bad Conductor- The objects which do not transfer heat easily. Ex- Wood, Air, etc. Thermal Insulator- No heat is transferred by any means. Ex- Abonite, asbestos etc.	When molecules are heated they headed upward and upper molecules go downward and this cyclic process continues.   Boiling of fluid	Heat travels in terms of energy packets or waves The heat absorbed by body gain energy   Radiations of Sun