It is toxic to mucous membranes.

it requires large displacement per TR compared to fluoro carbons.

It reacts with copper and its alloys.

all of these

same as

lower than

higher than

none of these

radiators in automobile

condensers and boilers in steam plants

condensers and evaporators in refrigeration and air conditioning units

all of the above

parallel flow

counter flow

cross flow

all of these

A grey body is one which absorbs all radiations incident on it.

At thermal equilibrium, the emissivity and absorptivity are same.

The energy absorbed by a body to the total energy falling on it, is called emissivity.

A perfect body is one which is black in colour.