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Step 3: Resistance

The next very important consideration to keep in mind is that electricity in a circuit must be used.

For instance, in the circuit above, the motor that electricity is flowing through is adding resistance to the flow of electricity. Thus, all of the electricity passing through the circuit is being put to use.

In other words, there needs to be something wired between positive and ground that adds resistance to the flow of electricity and uses it up. If positive voltage is connected directly to ground and does not first pass through something that adds resistance, like a motor, this will result in a short circuit. This means that the positive voltage is connected directly to ground.

Likewise, if electricity passes through a component (or group of components) that does not add enough resistance to the circuit, a short will likewise occur (see Ohm's Law video).

Shorts are bad because they will result in your battery and/or circuit overheating, breaking, catching on fire, and/or exploding.

It is very important to prevent short circuits by making sure that the positive voltage is never wired directly to ground.

That said, always keep in mind that electricity always follows the path of least resistance to ground. What this means is that if you give positive voltage the choice to pass through a motor to ground, or follow a wire straight to ground, it will follow the wire because the wire provides the least resistance. This also means that by using the wire to bypass the source of resistance straight to ground, you have created a short circuit. Always make sure that you never accidentally connect positive voltage to ground while wiring things in parallel.

Also note that a switch does not add any resistance to a circuit and simply adding a switch between power and ground will create a short circuit.
<p>supr</p>
<p>For any soon-to-be electronic enthusiasts, &quot;Arduino&quot; is something for you to look into.</p>
<p>I totally agree. <a href="http://amzn.to/1sa0y8O" rel="nofollow">There is a great 'starter kit' on Amazon</a> that includes a full color manual. </p><p>I bought this for my Son and he had a great time going through all the different tutorials!</p>
<p>Nice kit, but I would recommend the new <a href="http://www.amazon.com/dp/B01EKO6FZU" rel="nofollow">Make: Electronics Component Kit 2nd Edition</a> for a beginner in the field as it will teach them all of the circuits and electronic theories they need to know before getting into Arduinos. This kit has all the components for the beginning of the new Make: Electronics 2nd ed book which is the best book for newcomers looking to learn electronics and build circuits.</p>
<p>Yeah, this is a good kit. Not having the additional complexity of learning Arduino code is a plus for sure.</p><p>But, you can't go wrong with either kit! :)</p>
I'm starting out in electronics and on a schematic when a wire seems to split off two ways on a right angle that just means it is connected to both of those components correct?
<p>Hi !</p><p>I am vinay and I want to enlighten a 12 LED by the battery of my bajaj caliber 115 motorcycle, I want to know how can I use CD 7812 voltage regulator to get a constant 12 V DC while the bike is running ( when it will produce around 14.5 V).</p>
when you say ground do you mean negative<br>
Expertman, In early Electronics, ask about anything that you feel uncertain about. Its a &quot;grey&quot; area, an important question. In response, &quot;Ground&quot; and &quot;Negative&quot; are used with the same intent.They refer to the &quot;polarity&quot; of the power supply(Battery in this case) and where the 'pin' of a component's intended destination is(These components are usually labeled with this, if necessary) if unsure, find it online-(Not in a 'Blog', use 'DIGIKEY') Great prices, too!<br>. Good luck, hope this helped!
<p>i guess in both images,, wires are connected in parallel...</p>
i've been looking for this all over the endless fields of the internet. so, just tanks a lot
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<p>apt site for beginners</p>
<p>This was very educational and informative for me thanks</p>
<p><strong>nice site for beginners as well as professionals</strong>.</p>
<p>Michael U.</p><p>Thanks alot for this tutorial, it is so rich</p>
<p>Hi,<br><br>Thank you so much for this tutorial.<br><br>FYI , on step12 (ie LED) you mentioned that the flat notch indicator is on anode end , but its on cathode end of the LED. Please check it.<br><br>Thanks.</p>
<p>Thanks for this tutorial!<br><br>For all electronic fans, I made a site about basic stuctures used in analog electronic:<br><br><a href="http://shematronic.ddns.net" rel="nofollow">http://shematronic.ddns.net</a></p>
<p>I appreciate this tutorial. However, where can I go, not to find circuits, but more specifics on how circuits work. I can understand how the first circuit works , sort of understand how and why the second circuit works, and am more lost on the third one. I'd like more of an explanation on why resistors and capacitors are used in specific situations. Any suggestions?</p>
<p>For the &quot;Your second circuit&quot; section, is it 2N3906 PNP and 2N3904 NPN or should the PNP and NPN be switched? The parts list does not match the image of the circuit. </p><p>I'm a beginner, and I want to make sure I use the correct parts.</p><p>Thanks</p>
thanks... good for start<br>
<p>Thanks, this was exactly what I needed. A nice improvement would have been to explain why each element was on the circuit, instead this feels like you just follow instructions without knowing what you are doing. But once again, it's a perfect introduction to ultra beginners like me.</p>

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Bio: My name is Randy and I founded the Instructables Design Studio. I'm also the author of the books 'Simple Bots,' and '62 Projects to ... More »
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