energy Flashcards
In what two ways can work be done?
Mechanical and electrical.
In what ways can energy be transferred?
Mechanically, electrically, by radiation, by heating , by sound or light wave.
What is kinetic energy?
Energy it possesses due to its motion.
What 2 factors affect kinetic energy?
Speed and mass.
What is internal energy?
The total energy stored by the particles making up a substance or system.
What is specific heat capacity?
The amount of energy needed to raise 1kg of a substance by 1 degree.
What is the conservation of energy principle?
energy can be transferred usefully, stored or dissipated, but can never be created or destroyed.
What is the difference between a closed system and an open system?
An open system does exchange energy and matter with its surroundings. A closed system doesn’t exchange energy or matter with the surroundings.
What are the 3 ways of heating? And where are they seen?
Radiation (empty space), conduction (solids), convection (fluids).
How does heating by conduction work?
vibrating particles transfer energy to neighbouring particles.
What is thermal conductivity?
How well an object transfers energy by conduction.
What is meant by the term ‘fluid’ and what states is this?
Where the particles are free to move. Gasses and liquids.
How does conduction work?
As one end of a solid object is heated, energy is transferred to the kinetic energy stores of the particles in that end. This causes the particles to vibrate faster, and so they collide with their neighbouring particles more often. As the collisions transfer kinetic energy, their neighbours also vibrate faster and collide more often with their neighbours. This process repeats over and over again so that energy is effectively passed along the object from one particle to the next.
