10 Common Beginner Circuit Mistakes

This video goes over 10 common mistakes I've seen students (and adults!) of all ages make when working with beginner circuit projects. Don't hesitate to leave a comment if you have a question!
0:00 intro
0:42 wrong breadboard row
2:37 wrong polarity (components backwards)
4:02 parts not pushed into the breadboard all the way
5:56 messy breadboard wiring
8:19 not using power buses
9:59 multimeter probe in wrong port
11:53 wrong multimeter dial setting
13:54 connecting probes to circuit wrong
17:43 misunderstanding open circuits
21:03 misapplication of Ohm's Law
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[@Hidegety1]

Your explanation of mistake 5 was kinda ahaa moment for me -> several things clicked into place. Thank you for the revelation.

[@Flowspinner]

Your videos are really helpful! It's awesome that you take time out of your day to make them for us. Thanks!

[@simpjkee]

18:58 - I did a very short electronics course in 5th or 6th grade. Other than that, I am learning all this for the first time at age 42 so I appreciate these kinds of very basic tutorial type videos. Here's why this part is confusing. You say we use Ohm's Law here to calculate the voltage at that corner. You do Ohm's Law and the answer is V(or volts)=0. Then you do the quick verbal switcheroo and say that the "Voltage Drop" is 0 and therefor V(or volts) is actually 3 even though we just calculated it using Ohm's Law and Ohm's Law said it was 0. This is where the confusion lies. If current was.... lets say... 2 and resistance was... lets say.... 3, then you would say V(or volts)=6. You would not say the "Voltage Drop" is 6. So it seems the V in Ohm's Law sometimes means "Volts" and other times means "Voltage Drop". Perhaps it means "Voltage drop" only when you already know the voltage being supplied? Or only when IxR=0? Or when it's just 1 resistor in a circuit? I think I understand why the voltage would be 3 in this case, but the math looks goofy and the equation makes no sense... in this case. Or may be it's just the verbage of "Volts" or "Voltage Drop" makes no sense. This seems to be a very basic beginner issue, but I still haven't seen any explanation for it other than presenters just switching the verbage from "Volts" to "Voltage Drop" to explain the weird math and why V=0 is actually V=3.

[@BenFinio]

Hi - sorry for the confusion, you are correct that playing fast and loose with the terms "voltage" and "voltage drop" can be confusing for beginners. Technically speaking voltage is ALWAYS measured between two points, so you are always referring to the "drop" between those two points. However, in simple battery-powered circuits like this one, if you just say "voltage" it is implied that you mean the voltage relative to ground, where "ground" is the reference point you define as zero volts - in this case the negative terminal of the battery. I have a full introduction to circuits playlist that goes more into the math behind all this that may be more helpful in clarifying these issues: kzbin.info/aero/PLKL6KBeCnI3U6KNZEiitdtqvrxkBhpuOp&si=vJDFdkxTX-RD7nYO

[@chromerims]

Really helpful are: 9. Misunderstanding open circuits 10. Misapplying Ohm's law Thank you.

[@matijaderetic3565]

Thank you for this very helpful video. I would like to suggest where confusion comes from at 18:50 open circuit voltage explanation. Voltage is DIFFERENCE in potential energy. You need two points to compare. Talking about a single point leaves the listener without a reference. In your explanation 0V is from negative to another point on negative side and 3 V is from a point of positive to another point on negative side.

[@jeffg4686]

Great video. Just getting back into circuit stuff and this helped a lot.

[@CorryTerblanche]

Thanks, your videos are awesome and easy to understand!

[@BenFinio]

Thanks, glad they're helpful!

[@lepre4720]

Very helpful and just a well done video. Thank you a lot.

[@BenFinio]

Glad it was helpful!

[@daz41262010]

very cool to see all these common mistakes :)

[@JSPUFC]

Thank you

[@GripFreak]

Hi Ben, great channel! Can you recommend a breadboard electronic kit to get started making common circuits? Thanks in advance! Subscribed!👍

[@BenFinio]

The SparkFun Inventor's Kit for Arduino is great if you would also like to get into Arduino and programming. Otherwise, there will be tons of kits on Amazon (with or without Arduino), I have not tested them but I don't think you can really go wrong with them. (sorry for the super delayed reply, KZbin stopped sending me comment notifications!)

[@psiddarth3581]

Great video

[@BenFinio]

Thanks!

[@psiddarth3581]

@@BenFinio 😁

[@alikaampo9370]

Thanks it helps me, my question is that all the components will measure same LED, Motor and so on. I tried to measure current and voltage LED it worked but motor worked same method with voltage two connection of the LED voltage as well as current. Was that accurate or is there any other method? Many thanks

[@alikaampo9370]

Other than that, how to find unknown voltage and current without datasheet, can you make close circuit high or low.

[@BenFinio]

@@alikaampo9370 Hi Ali - I don't fully understand your questions but I'll do my best to answer. To measure the voltage across a two-wire device, you always put the multimeter probes in parallel (one to each wire). This is the same for a motor, an LED, a resistor, etc. To measure the current through a two-wire device, you always put the multimeter probes in series. Again this is the same whether you are measuring a motor, LED, resistor, or anything else with two wires. I don't understand your question about finding unknown voltage and current without a datasheet. What type of part are you referring to?

[@alikaampo9370]

@@BenFinio thank you Ben, my point is that I have universal motor without label or without details of value and current value therefore what can I do and how can I to ru the circuit? Many thanks

[@BenFinio]

@@alikaampo9370 in that case I think your safest bet is to start with a lower voltage and gradually work your way up. If it is a small hobby motor then many of them operate in the 3-6V range. If you start out with 12V or 24V right away you may damage the motor.

[@davenelson8187]

In step 5, you appear to have a 6v power supply (4x1.5v batts) powering 6 LEDS with a combined min. Voltage requirement of 13.4v (2R@3.4v, 2Gr@6.4v and 2Y@3.8v)? How is this possible, since there should not be enough power available to light them all adequately? I must be missing something? I’m currently struggling with this same type of problem trying to light 8 various color LEDS using one or more 9v batteries 😢

[@BenFinio]

The LEDs are in parallel, not series, so their voltages do not add like that. This video may be helpful: kzbin.info/www/bejne/e5ammWlulpZ6e8k

[@daz41262010]

cool :)

[@mindaugas9958]

Great video!! But you made a mistake with the LEDs, It should be yellow, green, red from the top not red, yellow, green 😅 kzbin.info/www/bejne/ZnzHkqZtbNWUj5Y

[@michaelhampton6993]

im sorry brother but its not 3 volts. your math was like a magicians slight of hand. not saying you did it on purpose or had any intent other than to teach but its not 3 volts. love you tho.

[@BenFinio]

This is a long video and it's been a while since I made it - can you tell me the timestamp for the part of the video you're referring to so I can check?

[@gamer.1773]

​@@BenFinio 18:50