sir issac newton discovered that any two masses m1 and m2 attract each other with a force that is equal in magnitude and acts in the opposite direction according to this relationship: F=(Gm1m2)/r^2. What is the appropriate unit for G if the preceding equation is to be homogeneous in units?

Water vapor initially at 10 bar and 400 °c is contained within a piston-cylinder assembly. the water lost heat to the surrounding according to isochoric (iso-volumetric) process until its temperature is 150 °c. the water is then condensed isothermally to saturated liquid. for the water as a system, calculate the work in kj/kg