Changes in Energy Flashcards

All 5 cards in this deck

What are the three ways the energy of a system can be changed?

By work done by forces, electrically (in electrical equipment), and by heating.

In a Sankey diagram, what does the width of each arrow represent?

The amount of energy transferred in that pathway.

What happens to the total energy in a closed system when energy transfers occur?

There is no net change — the total energy stays the same.

True or false? In a closed system, the useful output energy equals the total input energy.

False. Total output (useful + wasted) equals the input; useful output is less.

In physics, what is meant by a 'system'?

The single object, or group of objects, that you have chosen to study.