Which circuit is a series circuit?

Africtionless piston-cylinder contains 50 l of saturated liquid r-134a. the piston has a mass and an area resulting in an applied pressure of 500 kpa on the refrigerant. the refrigerant is now heated until its temperature rises to 70∘c. calculate the work (in kj) done during this process.

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

Scientific models are based on current knowledge, which can limit their effectiveness when new discoveries are made.