hi guys
Iam really new to the world of arduino and only know a bit of electronics which includes ohm's law and a bit more.I really liked the idea of using arduino.but before beginning I just wanted to know what knowledge of electronics in required in using arduino and making your own projects.
That very much depends on the projects. You can start with very little knowledge,
you can use an Arduino to help learn electronics...
You really need to know what a circuit is.
Some experience in connecting power supplies, switches, lamps and such.
Given that, it is a learning experience.
And - you have found the "General Electronics" thread. Look around and read - this is a "living" learn-as-you-go textbook.
If you're not sure of your knowledge start with a really basic book such as "Arduino for Dummies" it will introduce you to basic electronics and you can then get into something something deeper as needed. If you're serious you could then get yourself a decent text book.
You can learn a lot by dipping into forums and Google but you will have big holes in your knowledge.
Russell.
Ohm's law, Kirchoff's current and voltage laws, you should understand capacitors and inductors, basic semiconductors.
And... you should learn to draw schematic diagrams. The essence, in fact the purpose of schematics is clarity. Or we'd all just use pictorial diagrams.
See my signature lines for links.
These may help you learn:
https://learn.adafruit.com
https://learn.adafruit.com/search?q=Arduino
And a progamming language, if you know the basics of C you'll be fine.
I would offer that you know how to read and can learn.
it is hard to fill a cup that is not empty.
get any of the starter packs with the sensors or motors or such that serves you best.
you will learn some things by doing and will fill in the blanks as you go.
when you come here to ask, it is very helpful to us if you have a sketch of your circuit to show what you have wired.
we like hand sketches or PAINT or such. the one we do not like so much is the Fritzing prints. they are not very informative to us.
you only need to understand that if you can light an LED, then you can turn anything on or off. if you test for the LED, it is a simple step to get the 'other thing' to work.
Agreed. You don't need anything in the way of prior knowledge if you follow one of the simple tutorial books. You will learn what you need as you go. Yes, Ohm's Law is essential but you already know that. Don't worry about Kirchoff yet, it's really just common sense.
My advice, "Get stuck in". Don't be afraid to make mistakes just learn from them.
Bon chance.
Russell.
thanks everyone for all your advices.it really helped me a lot
but could you all tell me a good book I should buy to get a hang of things
If the questions asked on this forum are any guide, people aren't letting a lack of electronics knowledge stand in their way 
Crehan:
thanks everyone for all your advices.it really helped me a lot
but could you all tell me a good book I should buy to get a hang of things
I don't have a high opinion of book learning for hobbies - people often end up trying to do the exercises in the book, and lose interest in doing their own projects in the process, becuase they're turning a fun thing into something like school. I usually do better with jumping in (at least once the basics are done) when learning a new tool for creating stuff (electronics, software, physical objects, etc), and researching the parts I don't know online.
I completely agree with DrAzzy, the best way to learn is pick a project that you want to do.
Want to build your own irrigation timer? Or maybe a clapper for your light switches in the house? Maybe you need to check the moisture level of the soil in your lawn, or want to know the current temperature and humidity.
The gist of it is, pick a something that you want to do that involves electronics and programming. Start with something useful but relatively simple. Then break it into pieces, work on one small piece at a time, researching as you go. You'll be making progress so it will keep you interested, and the satisfaction you get at the end of the project is well worth the headaches!
If you try to sit down and 'learn it' before you ever start a project, soon you'll find an arduino sitting on a shelf covered in dust....
All of the previous comments are good advice but I would like to point out that the critical factor is knowing when you don't know...meaning knowing that you have no experience doing a particular task and taking the time to post on the forum for advice. As already mentioned, there is no shortage of electronics related questions from people with no experience who want to do something. By the same token, there is no shortage of people who underestimate the complexities of electronics and decide to just "wing it" and blow things up or fry chips or spend hours and hours troubleshooting the simplest problem. If you are not too proud to ask for help and know when you need to do that, you shouldn't have any problem. It's when you just start "guessing" without a proper background in the basics that you run into trouble.
We have encountered some very stubborn people who grossly overestimate their capability to solve problems for which they have no experience. To give you an example, if you take a tiny 2n2222 transistor or an 8-pin 555 chip and a 10A power supply that has no current limit adjust, and then wire up your circuit with some rookie mistake, the energy involved when using a 10A supply is such that these small devices can blow a small cone shaped crater hole in the devices and project that piece of plastic at a velocity that can send it shooting across the room
and bounce off at least one wall and wind up 30 feet from it's starting point or, alternately, the device can make a popping sound and a flame can shoot out of it
and you can watch it glow red as it melts down your breadboard as the PS delivers
10A through a direct short in the device. If there are any children standing in front of the breadboard when it blows, they could be blinded if a projectile fragment hits them in the eye. Try explaining to your wife that you just blinded your child. If you're lucky , it fails "open" but I have witnessed the two above scenarios first hand. The transistor piece bounced off 2 walls and a table and the breadboard burst into flames. What's the point ? Don't make assumptions about what is or isn't ok if you have no experience, especially when it comes to power supplies. You are much better off using AA battery packs than some surplus 10 or 20A ps that has no current limit adjust knob. If you have to use such a supply then add a 1/2A inline fuse holder. It's going to be very hard to convince friends and family that you know what you are doing if you start a fire in their house.
The transistor piece bounced off 2 walls and a table and the breadboard burst into flames
Seriously?
Your not exaggerating just a bit?
Seriously?
Your not exaggerating just a bit?
Not in the least. I heard a loud BANG ! immediately followed by the sound of a BB (which was the cone shaped 2.5 mm diameter piece of plastic that blew out the front of the transistor) hitting the wall furthest from me and then ricocheting off the adjacent wall and then skipping across the work bench and landing on the floor at the wall behind me. Total ballistic trajectory distance traveled : 10 ft + 8 ft +20 ft =
about 38 ft. The transistor had a tiny crater in the front exposing the junction inside.
Anyone who has witnessed this type of thing is familiar with everything I have described. If it had hit someone's eye in the first 3 ft of travel I can almost guarantee it would have lodged in their eyeball. As far as the breadboard, there was a phewwppht ! sound as a 2 inch flame shot out of the top of the 555 and a
column of smoke started rising as the chip glowed red. With no fuse and no current limiting, the 12V , 10A power supply tried to supply I = V/R = 12V/0.1 ohm = 120A across the junction of the inside of the 555 chip but since it was only a 10A supply that's all it could deliver. If you connect a nichrome wire across the output of a 12V , 10A supply you can watch it turn red hot. A chip is made of semiconductor materials and sealed in plastic so the excessive heat ignites the plastic which has reached it's spontaneous combustion temperature. There is nothing magic about any of this. It happens all the time under the right circumstances (which, in general, is when people make all the wrong decisions about how to build and power electronic circuits). I'd be willing to bet Russel has a few stories of things he's seen.
Rasch
I worked on mains for years mate and I have built a lot of power electronics systems, mains voltage inverters, rectifiers etc, I have blown up plenty of stuff in my time, I know about Ohms law and I also know a 12V 10A supply is not what you are describing
No ones denying parts get hot or that an exploding cap can take an eye if your in its path that is completely obvious, Its the burst into flames part thats most unbelievable, no disrespect but it is made of material that is flame retardant!
Ohms law doesn't cut the mustard Rasch, you can't do a transient analysis with Ohms law up your game and move onto differential equations, the natural solution as opposed to the steady state solution
The 555 chip did get red hot and whether it was the breadboard or the chip that burst into flames is beside the point. It was indeed a 12V , 10A supply. There is no reason to think that I would just make this story up. An LM555 plastic case may or may not be flame retardent but when you put it on a plastic breadboard and short it out with a 120W supply you can indeed get flames.
Ohms law doesn't cut the mustard Rasch, you can't do a transient analysis with Ohms law up your game and move onto differential equations, the natural solution as opposed to the steady state solution
This is an absurd comment. The point was the amount of power. There is absolutely no reason to use transient analysis or differential equations to discuss how much power a circuit generates. I don't know what prompted such a comment but it makes no sense, especially the part about Ohm's law not cutting the mustard. 95% of everything in electronics can be handled with ohm's law. To suggest that it is has no value is just ridiculous. Why don't you show us how you would use differential equations to show the OP that 68W isn't a "serious amount of power".
I worked on mains for years mate and I have built a lot of power electronics systems, mains voltage inverters, rectifiers etc, I have blown up plenty of stuff in my time, I know about Ohms law and I also know a 12V 10A supply is not what you are describing
I described what I saw. You can believe it or not. If you don't believe me then why don't you get a 12V , 10A supply with no current limiting and connect it to an LM555 and short pin-3 (output) to GND and see what happens.
raschemmel:
I'd be willing to bet Russel has a few stories of things he's seen.
Oh yes!
Electrolytic capacitors and even NiCd cells unwinding themselves as they flew across the lab, various components bursting into flames emitting noxious fumes. The worst ones were the old selenium rectifiers which made a smell somewhere between rotten eggs and garlic as they destroyed themselves.
My first close call came when as a 15 year old schoolboy I worked on Saturdays in the workshop of a local radio and TV shop repairing radios and audio equipment. Many radios needed an external aerial and it was common practice for a quick check to hold a small screwdriver by the blade and touch it to the aerial socket to see if there was any response. On this occasion the radio was powered by directly rectified ac mains - no transformer and just isolating capacitors on the aerial socket. Well, as you've guessed, the capacitor was faulty and I got a hefty belt of 240 V. The involuntary muscle spasm sent the screwdriver across the room, narrowly missing the senior technician's ear before embedding itself in the wall!
Take care.
Russell
russellz:
My first close call came when as a 15 year old schoolboy I worked on Saturdays in the workshop of a local radio and TV shop repairing radios and audio equipment.
Wow! Those were the days. When they had radio and TV repair shops ...
Resinator:
No ones denying parts get hot or that an exploding cap can take an eye if your in its path that is completely obvious, Its the burst into flames part thats most unbelievable, no disrespect but it is made of material that is flame retardant!
Flame retardant does not mean that it will not burn. It means that it resists the propagation of flame to a certain extent. Get epoxy resin hot enough and it will burn. Don't ask how I know 
Russell.