Two boxes of mass m and 4m are in contact with each other on a frictionless surface. What is the acceleration of the more massive box?
1 point
4 m
F.
ות
F/m
F/(3m)
O F/(4m)
O F/(5m)

Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. initially, air is at 400 kpa and 17°c. the paddle wheel is now turned by an external electric motor until 75 kj/kg of work has been transferred to air. during this process, heat is transferred to maintain a constant air temperature while allowing the gas volume to triple. calculate the required amount of heat transfer in kj/kg.