Solution Practice Problem: Charge on each Plate Solution Occasionally, we also describe capacitors their charge density. We use the symbol for this. It is, very simply, the amount of charge per area on a plate. If we know the charge on one of the plates, we can calculate the electric field between them using the equation: Potential and Potential Energy in Capacitors On the last level, we discussed how much energy it took to move a particle in an electric field from one position to another. How do we do that in a uniform magnetic field? In some ways, this is actually easier. We use the equation: Where F is the force, and d is the distance you move the charge. In a uniform electric field, the E is constant, so we can now use the equation: or Plugging this in, we get, Hold that thought for a second. We are going to come back to it. In the previous section, we also learned that when we drag an object from point A to point B: We should also recall that Therefore: When we talk about the parallel plates, what causes the potential difference between them? The battery. So the potential difference between the plates is the same as the voltage on the battery. Because of this, we often abbreviate as V, because we are talking about the voltage on the battery. Now, let’s return to the equation we found before: If we combine this with the other equation, we get:
Solution Practice Problem: Charge on each Plate Solution Occasionally, we also describe capacitors their charge density. We use the symbol for this. It is, very simply, the amount of charge per area on a plate. If we know the charge on one of the plates, we can calculate the electric field between them using the equation: Potential and Potential Energy in Capacitors On the last level, we discussed how much energy it took to move a particle in an electric field from one position to another. How do we do that in a uniform magnetic field? In some ways, this is actually easier. We use the equation: Where F is the force, and d is the distance you move the charge. In a uniform electric field, the E is constant, so we can now use the equation: or Plugging this in, we get, Hold that thought for a second. We are going to come back to it. In the previous section, we also learned that when we drag an object from point A to point B: We should also recall that Therefore: When we talk about the parallel plates, what causes the potential difference between them? The battery. So the potential difference between the plates is the same as the voltage on the battery. Because of this, we often abbreviate as V, because we are talking about the voltage on the battery. Now, let’s return to the equation we found before: If we combine this with the other equation, we get:
notes_capacitors_level_4.docx