A system releases 141 kJ of heat to the surroundings and does 40. kJ of work on the surroundings...?

Question

What is the change in energy?

Answer 1

change in energy= work + heat

since the system did work on the surroundings, the value for work is negative (the system had to give up energy to do the work)

since the system released heat to the surroundings, the value for heat is negative (the system had to give up energy in order to heat the surroundings)

thus, change in energy= (-141kj)+(-40kj)= -181kj

Answer 2

I do not know yet. I think both heat and cold would effect ones comfort as we age because the built in thermal control does not work as well. Some people would be bothered by cold while others would be bothered by heat. I think the body mass impacts the body's ability to deal with cold and heat.