How should be the socket arrangement to connect appliances that should run only when they both are pluged in ? how the sockets are connected at our home and why?
Answers
Explanation:
They are connected in parallel. The reason for the parallel connection is that it results in each appliance operating at the same voltage (i.e., approximately 120V for line-neutral connected appliances, and 240V for appliances that are connected line-line) along the entire circuit. Each appliance/load draws from the source (the circuit supplied by the circuit breaker in the electrical panel) the current it needs to operate, based on its impedance, according to Ohm’s law: I = V/Z, where V is the circuit voltage and Z is the associated load impedance, and I is the current that the particular load will draw from the circuit, at the voltage (120 or 240V) supplied by the circuit. When the appliances/loads are connected in parallel, you can independently connect or disconnect any appliance/load from the circuit (and/or turn its associated power switch on and off), and the other appliances/loads on the same circuit will continue to operate normally, since they are all being supplied with the same (correct) voltage. The only time you get into trouble is if/when you connect too many appliances/loads to a single circuit, so that those loads collectively draw more current than what the circuit (and its associated circuit breaker) can safely supply. When this happens, the circuit breaker supplying and protecting the circuit trips, opening up the circuit. This causes all of the appliances/loads on that circuit to turn off, until you identify and unplug/disconnect the offending loads, reset the (tripped) circuit breaker that supplies that circuit, make a mental note to not connect that many appliances/loads to that particular circuit again, and you’re good to go.
If your residence were wired so that the appliances/loads were connected in series, you would also be connecting the impedances of those appliances/loads in series, and the voltage that would be available to each appliance would now be dependent not only on its impedance, but the impedance of every appliance in the series string. For example, let’s say you took two identical 100W, 120V lamps and connected them in series on a single 120V circuit. Each of these lamps has a full-load impedance of 120^2/100 = 144 ohms ** (Ohm’s law also stipulates that Z = V^2/P). If you connected the two lamps in series (note, you’d have to close/turn both of their control switches on first, otherwise neither lamp will operate), you would then have only 60V (120V/2), rather than 120V across each lamp. The power each lamp would then consume in this configuration would be P = 60^2/144 = 25W **. In other words, connecting both lamps in series would reduce their power output by a factor of four (it drops by a factor of four instead of two, because power varies with the square of the voltage). In addition, the moment either lamp is turned off, it would also disconnect power to the other lamp (as well as anything and everything else in the series string).
Much the same results would occur if you were to connect any other identical loads in series across a source voltage at which either one was designed to operate. I could give countless examples, with lots and lots of calculations, to illustrate how the voltages would divide for more than two dissimilar appliances in series, but hopefully you see that connecting appliances in series would NOT be a viable way to operate them.
** For those readers who correctly observe that the impedance of an incandescent lamp is dependent on the filament temperature, which is dependent on the power being dissipated by the filament, which is dependent on the current flowing through it, the filament resistance of the lamps when they are connected in series, will be different than their resistance when they are connected in parallel, and thus the voltages associated with the series/parallel connections outlined above, will be somewhat different than what I’ve calculated in the example. I’ve treated the lamps as having constant resistance filaments, in order to make the series/parallel connection comparison more understandable to the lay reader.
Answer:
They are connected in parallel. the reason for the parallel connection is that it results in each applinces operating at same voltage(i.e approximately 120 v for line neutral, connected applinces that are connected line- line ) along the entire circuit