Energy Production notees

Green house effect

Law of conservation of energy:

“Energy cannot be created or destroyed, only transformed from one form of energy to another.”


Intensity:

Rate of energy per unit area of imaginary sphere, inverse square relationship


Stars:

Power is luminosity

Intensity is apparent brightness



Black Bodies:

Constant temperature radiates and absorbs all (electromagnetic radiation and addition) at the same rate

Hotter objects peak at higher intensity and wavelength

Peak wavelength changes from red to blue

As temperature increases intensity of each wavelength increases, luminosity per square meter increases, peak is skewed to shorter wavelength


Gray bodies:

Most object are gray bodies

At a specific temperature will emit less temperature than a black body

Some energy is reflected not absorbed

Ratio of this different is emmisivity (power emitted by grey body/ power emitted by black body)


Albedo:

Extent of which a surface can reflect albedo is equal to 1- emmisivity d vice versa


Chlorophyll in planets evolved to absorb solar energy with the highest intensities the most efficiently


The solar constant is the total power reaching the earth’s atmosphere per square meter (Intensity)

Slightly varies due ot 11 year cycle and elliptical orbit


Earth

Gray body absorbs electromagnetic radiation then emits infared radiation, as heat

Green house effect:

  • Main gases, CO2 Methane, Water Vapour, N2O and O3

  • There are three ways a gas molecule such as CO2 can absorb energy from infrared (IR) radiation: vibration, translation, and rotation.

  • The natural resonant frequency of greenhouse gases are in the infrared (IR) spectrum.


Induction

EMF is energy form to turn into electricity


Electromagnetic induction:

  • Movement or change in a magnetic field relative to a stationary charge giving rise to an induced current/voltage


When a conducting rod moves through a magnetic field it causes positive and negative charges to separate and induce an electromotive force (emf)

The charges accumulate until the attractive electric force that they exert on each other equals the magnitude of the magnetic force


Induced current:

  • Creates by emf has to be halfway through

  • caused by a changing magnetic flux (partway through a magnetic field or moving through a magnetic field)


Flux (Φ)\left(\Phi\right)

  • Flow of something

  • Magnetic flux density (Wbm-2) (T) is numerically equivalent to magnetic field strength


Faraday law:

  • Calculates size of induced electromotive force


Lenz’s law:

  • Induced current and it’s magnetic field will have a direction that will opposet the change in flux that produced it.

  • Negative law in faraday’s law