The pole of a bar magnet can attract a piece of unmagnetised steel. Explain why
it cannot repel the piece of steel.

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.

What can you increase the strength of an electromagnet by

In which type of system is power held solely by the central government and not shared with regional governments? group of answer choices federal unitary confederate oligarchic