UTF-8In photo-voltaic cells as well as in the photosynthetic apparatus of chloroplasts in plants, the energy of light is captured and stored by using it to separate a negative charge from a positive charge. Separated charges are a way of storing energy at the molecular level, just as raising a heavy object from the Earth's surface is a way of storing energy -- think of water stored behind a high dam or a counterweight attached to a cable to help to lift an elevator.
How can this stored interaction energy be converted to other forms? Can it be converted to thermal energy for example?
Suppose we separate the charges as shown, by separating them by a medium consisting of cold (low thermal energy) molecules, and then at a particular instant we allow them to recombine.
Run the simulation to see what happens. Watch the plot to see how the Potential energy changes, as well as the kinetic energy of the neutral (Ws) molecules.
Did the Interaction
Energy increase or decrease? Did the average Ws Kinetic Energy increase or
decrease? Did the Total energy change? What Energy transfer occured?
Interaction Energy -- after the ions reach equilibrium. Did the
Interaction Energy increase or decrease when they ions bind to each other?
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Write down the starting Interaction (Potential) Energy (mostly due to the
separated ions) and starting Kinetic Energy of the neutral (Ws) molecules.
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After the simulation reaches equilibrium -- the ions will all be bound to
each other in a tiny "crystal" -- write down the Equilibrium Interaction
Energy and the equilibrium Kinetic Energy/Ws particle.
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Did the Interaction Energy increase or decrease? Did the average Ws
Kinetic Energy increase or decrease? Did the Total energy change? What
Energy transfer occured?
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falseorg.concord.mw2d.activity.AtomContainerStoring_Energy_separated_charges$0.mmlorg.concord.modeler.PageXYGraph0Time (fs)Total Energy/ParticleKinetic Energy/Particle CkPotential Energy/ParticleKinetic Energy/Particle Ws500350xy42045-1-1