There are few great 'Laws' in our text books. Newtons law, Einsteins theory of relativity, Fleming's Law etc. Most of the students of 2nd PU may know it. The question is that they can answer if anyone make those students to answer even at 12. What's the benefit he/she gets after reading! Believe me. Many of us do not know how to covert Km /hr to m/s . Few are in search of formula. Only thing what we require is Common sense. It is true that farmulas need to be learnt. You should know how the formula is derived as well. You should be able to find out the formula even if you forget it. If so, how should we read? In simple words we must understand Basics.
Ohm's law
What does it state? In a conductor if u double the potential across it , current also gets doubled. (In a conductor, the current flowing through it is directly proportional to the potential difference across it) You should have a strong grip over these subjects.
Current is nothing but the movement of charge. (flow of charge is current) In a conductor take a cross section area(A).Just find the no.of charges flowing across the area in 60 seconds. Divide the total charge by 60. You got the Current now!
how to measure Charge? Such questions in your head should come in. That's the time when you start finding out. Here you have an interesting thing. Those moving charges are positive/negative? I got to see 2 contrasting statements in 9th standard text book.
1) electrons move from negative end of the battery to the positive end. This current is called negative current.
2) positive charges move from negative to the positive end of battery. This is called positive current.
Ohm's law
What does it state? In a conductor if u double the potential across it , current also gets doubled. (In a conductor, the current flowing through it is directly proportional to the potential difference across it) You should have a strong grip over these subjects.
Current is nothing but the movement of charge. (flow of charge is current) In a conductor take a cross section area(A).Just find the no.of charges flowing across the area in 60 seconds. Divide the total charge by 60. You got the Current now!
how to measure Charge? Such questions in your head should come in. That's the time when you start finding out. Here you have an interesting thing. Those moving charges are positive/negative? I got to see 2 contrasting statements in 9th standard text book.
1) electrons move from negative end of the battery to the positive end. This current is called negative current.
2) positive charges move from negative to the positive end of battery. This is called positive current.
Among these two statements, i do not know to select one. Looks so contrastive. I'm sure that you are also confused. Positive charges are moving? Negative charges are moving? Or both? Beloved Physics lecturer had been taking class. That time i realised the fact that only electrons are moving not protons. Protons are very heavy. Mass of electrons are negligible
Electrons move like a drunker. Movement is not linear, but vectorial summation could be linear.
We know that electrons are the sole reason for current(i). Lets be positive. Imagine that electrons are stationary, equal amount of positive charges(q) are traveling in the opposite direction. Actually positive charges are not moving where as electrons are moving. Among a 2 statements above, both equally mean same thing. Direction of movement of the positive charges are taken as the direction of current(i=q/t). We measure charges in Coulomb. 1 Coulomb is that charge got by summation of charges of 6.25 × (10) ¹8 electrons.
"You should burn like Sun if you want to shine like Sun"said APJ. So we must work hard and smart and think in a different way to get success. What do you mean by Potential? "Potential is the driving force". Potential difference is the one which drives the electrons. When electron is under potential difference, it is said to have potential energy. Potential energy is stored energy which is converted into kinetic energy during movement.
"You should burn like Sun if you want to shine like Sun"said APJ. So we must work hard and smart and think in a different way to get success. What do you mean by Potential? "Potential is the driving force". Potential difference is the one which drives the electrons. When electron is under potential difference, it is said to have potential energy. Potential energy is stored energy which is converted into kinetic energy during movement.
What is Proportionality? Here potential (v) and the current (i) are directly proportional. i gets doubled if we double the v. Similar if tripled or halved also.
v proportional i
If you want to put '=' in between v and i , must multiply a constant either to v or i. Lets multiply a constant R to i.
v = iR
This constant R is called Resistance. It represents the resistance to the flow of electrons. It is measured in ohm.
v proportional i
If you want to put '=' in between v and i , must multiply a constant either to v or i. Lets multiply a constant R to i.
v = iR
This constant R is called Resistance. It represents the resistance to the flow of electrons. It is measured in ohm.
"A goal without a plan is just a wish". Please have a dream and try to chase it. Prepare a plan for that. Remember this is competitive generation. You need to face so many difficult exams like NEET, JEE etc. I think they are not that difficult if you have a depth of concepts.
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