Define heat, thermal energy, conduction, convection and radiation

Heat:  it is a form of energy associated with the movement of atoms and molecules in any material.The higher the temperature of a material, the faster the atoms are moving, and hence the greater the amount of energy present as heat. 

Thermal Energy: the internalenergy of an object due to the kinetic energy of its atoms and/or molecules. The atoms and/or molecules of a hotter object have greater kineticenergy than those of a colder one, in the form of vibrational, rotational, or, in the case of a gas, translational motion.

Conduction: the process by which heat or electricity is directly transmitted through a substance when there is a difference of temperature or of electrical potential between adjoining regions, without movement of the material.

Convection: the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.

Radiation: the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles that cause ionization.

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