Zusammenfassung der Ressource
Kinetic and Potential Energy Stores
- Movement means energy in a object's kinetic energy store
- Anything that's moving has energy in
its kinetic energy store
- Energy is transferred to the
kinetic store when an object
speeds up and is transferred
away when it slows down
- Energy in the kinetic
store depends on the
object's mass and
speed
- The greater the mass and the
faster it is, the more energy
there will be
- E(k) = 1/2MV^2
- Kinetic energy (j) = 1/2 * Mass (kg) * Speed (m/s) ^2
- Raised objects store energy in
gravitational potential energy
stores
- Lifting objects in a
gravitational field
requires work
- Causes a transfer of energy to the
gravitational potential store of the
raised object
- The higher the object is
lifted, the more energy is
transferred to the store
- The amount of energy in a G.P.E
store depends on the object's
mass, height and the strength of
the gravitational field the object is
in
- E(p) = MGH
- G.P.E (j) = Mass (kg) * Gravitational field strength (N/kg) * Height (m)
- Falling objects also transfer energy
- When something falls. energy from its
gravitational potential store is
transferred to its kinetic store
- For a falling object when
there's no air resistance:
- Energy lost from the G.P.E store =
Energy gained in the kinetic store
- In real life, air resistance
acts against all falling
objects
- Causes some energy to be transferred
to other energy stores
- E.G, the thermal stores of the
object and surroundings
- Stretching can transfer energy to elastic
potential energy stores
- Stretching or squashing objects can
transfer energy to its elastic potential
store
- So as long as the limit of proportionality has not been
exceeded, energy in the elastic potential store can be
found using:
- E(e) = 1/2KE^2
- Elastic potential energy (j) = 1/2 * Spring constant (N/m) * Extension (m)