Energy Stores and Systems

Flashcards covering key concepts of energy stores and systems as outlined in the lecture notes.

What are the 7 stores of energy?

Gravitational potential, Nuclear, Kinetic, Thermal, Elastic potential, Magnetic, Chemical.

What are the units of energy?

Joules, J.

What does the law of conservation of energy state?

Energy cannot be created or destroyed, only shifted between stores; the total amount of energy is always the same.

What does it mean when we say that energy is 'dissipated'?

That energy has spread out, usually to the thermal store of the surroundings.

What is a system in the context of energy?

An object or a group of objects.

What is an open system?

A system where external forces act and energy is dissipated.

What is a closed system?

A system where no external forces act and no energy is dissipated.

How many Joules are there in 1 kJ?

1 kJ = 1000 J.

How many Joules are there in 1 MJ?

1 MJ = 1,000,000 J.

What happens to the gravitational and kinetic energy stores when a ball is thrown upwards?

Gravitational store increases while kinetic store decreases.

What happens to the chemical energy store when coal is burned?

The chemical store of coal decreases.