#PARALLEL RESISTANCE SERIES#

This may mean that, as an approximation, we may be able to ignore the huge hose and only consider the tiny hose when trying to figure out the overall flow rate see Algebraic Approximations.

#PARALLEL RESISTANCE SERIES#

While the amount of water flow is the same, this does not mean the two series hoses necessarily have the same effect on the flow of water.ДЇor example, if we have a tiny (small diameter) hose in series with a huge (large diameter) hose, the tiny hose is going to have the dominant effect on restricting the flow of water, regardless of whether it comes first or second in the direction of the flow. In series means that the same flow (whether of charge or of water) must, by the layout of the system, go through all of the series components. WeвЂ™re assuming there are no leaks! But thatвЂ™s the point вЂ“ any possible leakage paths would have to be modeled as additional paths on the schematic, so the two hoses would no longer be simply in series. Now, if we connect a second hose to the exit of the first hose, the same current must flow through the second hose as flows through the first. The result is that even if the hose is 100 feet long, water essentially immediately starts coming out of the end because the hose was already pre-filled. if the faucet is opened wider, the faucet pushes more water into the start of the hose, which immediately pushes on the next bit of water, and so on, until it reaches the end. In the hydraulic analogy, imagine a garden hose thatвЂ™s already completely filled with water. (In reality, details like the speed of light mean this is not entirely instantaneous, but now weвЂ™re talking about issues far beyond the scope of this chapter!) Any accumulation of charge would repel other charges and diffuse. Why? Because no net charge can be stored within (or between) any circuit elements, ever. In the Lumped Element Model world of schematics, this is considered to happen instantaneously. That doesnвЂ™t sound so cool as an equation, but thatвЂ™s all that вЂњin seriesвЂќ means. There are a pair of nodes (or terminals) that are the start and end of the chain of series elements.ДЄny current that goes into the first terminal must exit the second terminal. Two or more components are in series if there are no side paths for current to enter or exit. If the hydraulic analogy doesnвЂ™t help your intuition, donвЂ™t worry about it вЂ“ you may have simply found a case where the analogy doesnвЂ™t hold up. It is actually possible to model real fluid systems with circuits, but it is a more subtle art than you may think at first, so just take what you can without dwelling on the details too much. It is often reasonable for an electrical engineer to look at a schematic and think about it like a plumbing problem: where will the water (charge) flow, and where are the pressure (voltage) drops? water) than of invisible electrons, so the analogy adds some value. Nonetheless, itвЂ™s easier for most people to visualize the motion of particles they can see (i.e. One issue is that many people also donвЂ™t have a good mechanical intuition about fluid flows, in which case the analogy doesnвЂ™t add any value. the water has to go somewhere!), and because pressure is a scalar potential energy (per unit volume) measure just like voltage is a scalar potential energy (per unit charge). The hydraulic analogy works because conservation of charge is quite like conservation of mass in a fluid flow problem (i.e. (Is a faucet a current source or a voltage source? What if thereвЂ™s air in the pipe?)

Many introductory texts attempt to use a hydraulic analogy of water flowing through a pipe, with flow rate representing current and pressure representing voltage.Д¬aution: this analogy works at a high level, but it quickly breaks down if you look too closely or ask the wrong many questions. These intuitions will be the building blocks of KirchhoffвЂ™s Voltage Law and KirchhoffвЂ™s Current Law. Solving resistor networks.Д«efore introducing the formal rules of how currents and voltages flow in circuits in general, letвЂ™s look at a common scenario to try to develop intuition at a higher level. Building intuition for series and parallel circuits.

Parallel resistance