An incident ray travelling in vegetable oil (n=1.47) strikes a boundary and enters an unknown medium with an angle of incidence measuring 25.0 degrees. It refracts at some angle away from the normal. Draw an approximate model of this example with appropriate angles and labels.

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.