Suppose that you are shopping in the mall around 7:00 p.m. on Christmas Eve. There are tons of last minute shoppers around when the fire alarm sounds. It turns out that there are only 3 doors to exit the ENTIRE mall from!
These three doors are set up in parallel. Or--
The three doors are set up in series.
Post which situation you would choose to exit through. Explain using at least 5 sentences, proper spelling and grammar, why you have chosen this situation and how it relates to Resistors in a circuit. Respond to at least one other classmate about their post.
2007-08-13 00:48:07 · 5 answers · asked by confused ~ 1 in Science & Mathematics ➔ Physics
If the doors are in parallel (i.e. side-by-side), then a person can exit through any one of them and be outside. If they are in series, then they must pass through the first, then the second, then the third to be outside. Obviously, the preferred exit scenario is the parallel bank of doors... you'll get out in 1 third the time.
In electrical circuits, the resistors are like the doors. In a series of resistors, the current must flow through the first, then the second, then the third. The total resistance to the flow is the sum of the resistors' impedances.
In a parallel set of resistors, the current can flow through any one of the resistors. If they have different impedances, then the current will flow through each in proportion to the resistances. For example, with 3 resistors of 100, 200, and 300 ohms, only 1/3 the amount of current will flow through the 300 ohm resistor as through the 100 ohm resistor, and only 1/2 the amount of current will flow through the 200 ohm resistor as through the 100 ohm one.
2007-08-13 01:03:56 · answer #1 · answered by ianmacpherson55 3 · 2⤊ 0⤋
Resistors in series you add up, resistors in parallel you take the inverse of the summation of the inverses.
This relates to your situation in that the more the resistance, the longer it will take to exit the mall.
I would definately want to be in a mall with 3 exit doors in parallel. It will take much less time for all the people to exit the building when there are 3 doors for everyone to exit than to have 1 door for everyone to fit in and have to go through another 1 door and then another.
Just picture people as current.
I hope you understand now.
2007-08-13 01:50:48 · answer #2 · answered by Mixed Asian 5 · 0⤊ 0⤋
Suppose that through each door 3 persons can exit per second.
If the doors were parallel, then, [3 x 3 = 9], nine persons can exit in a second. If there were nine hundred persons in the mall then it will take a total time of 100 second for clearing out off the mall.
If the doors were series, then each person has to go through each door before exit the mall.
In each second three persons will be leaving the last door. For the nine hundred persons to leave the mall it will take a total time of 300 seconds.
If we take this phenomenon as analogous to resistances in circuits, in parallel circuits the number of charges crossing any surface per second will be more than in series circuits.
Or the total current will be more in parallel circuit than in series circuit.
2007-08-13 07:04:07 · answer #3 · answered by Pearlsawme 7 · 0⤊ 0⤋
The question doesnt really make sense with respect to resistors. A series circuit involves voltage drops, this is is not analogue to the exit scenario that involves back to back doors. Besides three series doors make it effectively a single door exit.
The obvious choice is the parallel doors. That allows greater volume of shoppers out at the same time. Or in other words a current divider.
2007-08-13 01:03:55 · answer #4 · answered by ? 6 · 0⤊ 0⤋
You already got 2 good answers. Obviously three parallel doors are better for emptying the hall (think of three parallel valves opened for emptying a tank). Three serial gates doesn't really make much sense except in terms of physical security and metal detectors etc.
The last sentence indicates that it is an assignment. Good luck.
2007-08-13 01:39:49 · answer #5 · answered by Swamy 7 · 1⤊ 0⤋