The moisture content in air (humidity) is measured by weight and expressed in pounds or .

Heat is added to a piston-cylinder device filled with 2 kg of air to raise its temperature 400 c from an initial temperature of t1 27 cand pressure of pi 1 mpa. the process is isobaric process. find a)-the final pressure p2 b)-the heat transfer to the air.

The sum of the normal stresses does not change as the stress state rotates through an angle. a)-trune b)- false

What is creep? what is stress relaxation?