Transistor as a voltage amplifier | Class 12 (India) | Physics

Transistor as a voltage amplifier | Class 12 (India) | Physics | Khan Academy

Рет қаралды 66,953

6 жыл бұрын

We will explore what it means to amplify a signal mathematically, and then see how our transistor does voltage amplification.
Learn the next topic here --www.khanacademy.org/science/i...
Class 12 Semiconductors: We cannot imagine our life without computers today. But what makes a computer tick? What's making this technology grow at such an exponential rate? It's all due to semiconductors. As unbelievable as that might sound, altering the properties of semiconductors allows us to build these computers. In this topic, we will explore the world of semiconductors. It's a journey from what semiconductors are all the way to creating building blocks of these computers.
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Created by Mahesh Shenoy

Пікірлер: 41

@tommymusiccovers4159 4 жыл бұрын

The best video about this subject so far I can find on KZfaq

@mip0 2 жыл бұрын

same

@user-lv7yw5ll7h 10 ай бұрын

I like the way you explain and calculate. I need more of these.

@zizo-ve8ib 3 жыл бұрын

Amazing job as always, but there really aren't enough topics for you, there's a lot more topics in this I need 🥺

@user-ov7kd5go8s 2 жыл бұрын

you are an amusig teacher. Thanks

@siddharthravichandran4210 4 жыл бұрын

khan academy is the best

@styzr 6 ай бұрын

Thanks. Best explanation

@adityayanbhardwaj7131 5 жыл бұрын

can you make the video on logic gates?

@zizo-ve8ib 3 жыл бұрын

Just a quick question though Isn't RB usually supposed to be greater than RC that should indicate a reverse amplification, or does beta make the change ?

@gagandeep5309 5 жыл бұрын

Nice explaination.... Basically... Purely based on mathematical analysis

@adithyankg4969 4 жыл бұрын

Pls make video of logic gate

@Hino_55 4 жыл бұрын

Great Explanation! Thanks Sir Mahesh! :)

@captainlouiz6411 3 жыл бұрын

Please, Could you tell me what the name of teaching tool or software? I really like it. It's very nice and great video.

@vinita7097 3 жыл бұрын

Its Sketchbook

@educationalchannel6704 5 жыл бұрын

what is meant by grounded,connected to the ground or a referrence point.

@milindsharma8106 5 жыл бұрын

when a circuit end is grounded/earthed it means it has an electric potential of 0V

@zizo-ve8ib 3 жыл бұрын

Yes and it's just a way to tell the voltage at a specific point in the circuit to make things easier, it doesn't matter which point in the circuit is grounded or if it even is grounded, just simplification

@piyushkumarsingh0694 6 жыл бұрын

I ve a question, In the circuit what is that + 3 V , Where does it come from?

@KhanAcademyIndiaEnglish 5 жыл бұрын

The +3V is the DC power supply. In simple terms it can be thought of as a 3V battery

@prakhargupta1409 5 жыл бұрын

I have a doubt sir. How does the voltage 0.7 remain constant ? I mean..isn't it changing with Vi ?

@udaykiran2798 5 жыл бұрын

That's very simple. It is the barrier potential. Under forward bias if the external voltage exceeds just the barrier potential the current shoots linearly. Thus even the potential changes a little the current is always the same maximum. Thus the base always stays at 0.7.

@sohan_89 3 жыл бұрын

0.7 V is the barrier potential at the junction of a typical PN junction, once the supply voltage increases beyond this, the voltage drop won't increase much from 0.7 V. Only current will increase. (This means resistance adjusts itself to maintain only 0.7 V drop across the junction). In metals resistance won't change much , so drop across the conductor changes.

@penumalasunitha14 3 жыл бұрын

@@udaykiran2798 hey... I have a doubt,please clarify, firstly, don't understand, what is the work with 0.7v there???... In previous videos it is mentioned that V input =0.7 v. But now.. I don't understand... There are two voltage... Separately Vi and 0.7.two voltages are there..... Why... Instead of 0.7 v... Why didn't they connect Vi directly to circuit??

@udaykiran2798 2 жыл бұрын

@@penumalasunitha14 hi sunitha, i request you to go and check your connections with barrier potentials of semiconductors, if that doesn't clear your doubt then i will surely help you.

@RohitSaini-xn2vd 2 жыл бұрын

@@udaykiran2798 I have a doubt that the vin is alternate voltage so when it is between 0 to 0.7V it acts as off switch so how would it amplify the input voltage

@iandecker8157 5 жыл бұрын

What if I want the output voltage (V_o) to be equal to the input voltage (V_i) multiplied by a constant (k), and not just their deltas? i.e. V_o = k * V_i

@bhaskarpandey8586 5 жыл бұрын

You should not do this. But if you really want to relate them without deltas then your equation will be like V_o = k*V_i + c

@bhaskarpandey8586 5 жыл бұрын

Remember there is no fixed 0 potential , we define it on our comfort.

@chandanaroy2462 2 жыл бұрын

Probably literally the only vid online explaining input and output properly without asking me to mug up CE BE ICE IBE ABCD ETC. BECAUSE OH MY GOD WOULD IT PAIN THE PHYSICS BOOK AUTHORS TO USE LESS CONFUSING TERMS UGHH

@niranjan7457 3 жыл бұрын

Sir, I can't understand this part : 11:24 (Higher potential drop, lower potential drop)

@jagruti_b Жыл бұрын

They've explained more clearly the relation of Vi and Vo here: kzfaq.info/get/bejne/mdt_eaqQrrmsnqM.html They've also explained about those voltage drops

@hussainrassiwala2132 5 жыл бұрын

how can you take voltage drop from +3v to Vo since Vo is the amplified voltage and will be much higher than +3v supply

@KhanAcademyIndiaEnglish 5 жыл бұрын

Could you elaborate your doubt please? I am guessing the doubt is how is the output voltage only 3V? The amplification requires electrical energy. That energy is given by the supply. So if the output supply voltage is 3V, then the maximum output voltage cannot exceed 3V

@hussainrassiwala2132 5 жыл бұрын

@@KhanAcademyIndiaEnglish I am only telling that if the amplification of voltage is done from i/p to o/p then how could there be a drop from +3v to amplified output