Cells, EMF, terminal voltage & internal resistance | Electric current | Physics | Khan Academy

EMF is the work done by the cell in moving a coulomb of charge across its terminals. It represents the energy transferred per coulomb to the charges. Some of this energy is lost as heat due to internal energy. Hence the net energy gained by the charge = the emf - heat lost. This net energy gained per coulomb is called the terminal voltage. This is the voltage across the ends of the battery.

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Created by Mahesh Shenoy

[anubhavsharma]

This is how Physics should be taught!!
I was confused between them for a long time...but thank god I found your video..
thank you very much Khan Academy!

[VG__]

So practical, i would love to study entire physics if YOU are my physics teacher, literally ( not joking!) If You will teach me physics, I am ready to pursue physics as my career option🥺❤️

[sultanmahmud]

Man what are you made of
Simple things; many teacher blabbered in my life but nobody cleared the concept.
Thank u man.

[pingu]

My textbook did an atrocious job at explaining this, but you have made it super clear! Thank you so much. 🌸🌸

[phlegmsmoothie]

I had like to see the face of this angelic voice who helped us

[jays]

A very helpful Intuitive explanation of the topic. This helped a lot, thanks!

[dikshajain]

14:07 a whole lot!
You are a great teacher sir. Explained everything like butterflow :)

[rayanalive]

SUCH AN UNDERRATED VIDEO! The explanation was comprehensive & intuitive, and hats off for being such an adept teacher!

[studyaccount]

Mahesh sir and Khan Academy have had an incredible impact on my education and my life. Mahesh sir taught me with clarity and passion, while Khan Academy was my go-to resource for everything. As I move forward, I will carry their inspiration and lessons with me always. I am forever grateful to them. 🌟

[EhsanAmini]

Great video as always. Just one small point. When more current is drawn, the charges don't move any faster, but more charges are pumped per unit time. Current is the flow rate of charge (charge density per time) not its velocity. The travelled distance per unit time per charge (charge velocity) is not affected. More charges require more work (energy) to go through the internal resistor, and the more work is done per unit time, the greater amount of energy is lost as heat.

[benedictprajwal]

I had trouble understanding this in online classes, You people helped me a lot, Thank you so much

[treshanraoganni]

Honestly, i saw many videos on YouTube but this video and only this one has given me a lucid understanding of the concept. Heartfelt gratitude to you sir!

[Lava_ninjaa]

I was never explained it so well. Alas! Concepts aren't taught well in some institutions.
On the other hand, sir u have done an awesome job. Your a true gem. Understood it crystal clear.
Really appreciate.

[yaswanth_yaks]

Small video with lots of information.. thank you bro

[HarshitKumar-qs]

I am telling This is the best explanation I have seen about this topic in the entire feed

[chaoo_pukhrm_]

Which one to connect first the ammmeter or resistor to the positive terminal

[doer.me]

Many videos on this topic but it only this one where i understood. Thank you sir! Best Physics teacher with incredible content 🤩

[gamingwithshaurya]

Teachers like you give us clear understanding of physics.

[sujathah.s]

I was finding a great problem with emf and terminal voltage but now it's crystal clear

[gamingwithshaurya]

Such an underrated video this video give us clear understanding of voltage EMF but sir if please make a video on how is potential difference created inside a cell