Ohms Law
Ohms Law
We all have experienced the situation that when a torch is used for several weeks, its light becomes dim. We say that its cells have become weak.This means that the potential difference has droped to a smaller value because the chemicals have been used up in the chemical reactions. As the potential difference has dropped so less current flows through the bulb, and hence produces less light. So, we can say that the electric current passing through the circuit depends on the potential difference applied across it. The larger is the potential difference, the larger is the current. This relationship between potential difference and current was first discovered by a German physicist Georg Simon Ohm (1787-1854) and is stated by the law named after him
Ohm's Law states that the current passing through a conductor is directly proportional to the potential difference between its ends, provided the physical conditions such as temperature of conductor remain unchanged.
He further observed that as we increase the potential the current increases, so we can state that the
i.e., or
where R is a constant which is called resistance of the material.
Unit of resistance
The SI unit of resistance is ohm .
If I = 1 Ampere, V = 1 Volt, then R = 1 .
The resistance of a conductor is 1 ohm if a potential difference of 1 volt is produced across its ends when 1 ampere of the current flows through it.
The conductors, which obey the Ohms law are called the ohmic conductors or linear resistances. All metallic conductors (such as silver, aluminium, copper, iron , etc,) are the Ohmic conductors or linear resistances.
The conductors, which do not obey the Ohms law are called the non-Ohmic conductors or non-linear resistances. Examples are, diode valve, transistors, electrolyte, etc.
Illustration: A 5 V battery is connected to a 10 resistance. Calculate the amount of current flowing through the circuit.
Solution: It is given that
V = 5 V
R = 10
To find I =?
According to Ohm's Law
V = IR
Hence a current of 0.5 A flows through the circuit.
A solenoid is at potential difference 60 V and current flows through it is 15 ampere, then the resistance of coil will be _______________________ | |||
| Right Option : A | |||
| View Explanation | |||
Which of the following statements does not represent Ohms law-
| |||
| Right Option : D | |||
| View Explanation | |||
In a circuit n electrons flow through the cross section of a wire in t s when a potential difference V is applied. Write the following steps in sequential order to determine the electric resistance of the wire. (A) Determine the value of electric current , I=ne/t. (B) Note the value of Potential difference V, number of electrons n, time t and the charge e of an electrons. (C) Write the relation, V = IR. (D) The resistance of the wire , R = V/I
| |||
| Right Option : A | |||
| View Explanation |
Students / Parents Reviews [20]
A marvelous experience with Abhyas. I am glad to share that my ward has achieved more than enough at the Ambala ABHYAS centre. Years have passed on and more and more he has gained. May the centre flourish and develop day by day by the grace of God.
Archit Segal
7thAbhyas academy is great place to learn. I have learnt a lot here they have finished my fear of not answering.It has created a habit of self studying in me.The teachers here are very supportive and helpful. Earlier my maths and science was good but now it has been much better than before.
Barkha Arora
10thMy experience with Abhyas Academy has been very good. When I was not in Abhyas whenever teacher ask questions I could not speak it confidently but when I came in Abhyas, my speaking skills developed and now I am the first one to give the answer of teachers question.
Upmanyu Sharma
7thBeing a parent, I saw my daughter improvement in her studies by seeing a good result in all day to day compititive exam TMO, NSO, IEO etc and as well as studies. I have got a fruitful result from my daughter.
Prisha Gupta
8thThird consective year,my ward is in Abhyas with nice experience of admin and transport support.Educational standard of the institute recumbent at satisfactory level. One thing would live to bring in notice that last year study books was distributed after half of the session was over,though study ...
Ayan Ghosh
8thIn terms of methodology I want to say that institute provides expert guidence and results oriented monitering supplements by requsite study material along with regular tests which help the students to improve their education skills.The techniques of providing education helps the students to asses...
Aman Kumar Shrivastava
10thMy experience with Abhyas is very good. I have learnt many things here like vedic maths and reasoning also. Teachers here first take our doubts and then there are assignments to verify our weak points.
Shivam Rana
7thMy experience with Abhyas academy is very good. I did not think that my every subject coming here will be so strong. The main thing is that the online tests had made me learn here more things.
Hiya Gupta
8thAbhyas institute is one of the best coaching institute in the vicinity of Ambala Cantt area. The teachers of the institute are well experienced and very helpful in solving the problems of the students.The good thing of the institute is that it is providing extra classes for the students who are w...
Aman Kumar Shrivastava
10thAbhyas Methodology is very good. It is based on according to student and each child manages accordingly to its properly. Methodology has improved the abilities of students to shine them in future.
Manish Kumar
10thAbhyas is a complete education Institute. Here extreme care is taken by teacher with the help of regular exam. Extra classes also conducted by the institute, if the student is weak.
Om Umang
10thIt has a great methodology. Students here can get analysis to their test quickly.We can learn easily through PPTs and the testing methods are good. We know that where we have to practice
Barkha Arora
10thOne of the best institutes to develope a child interest in studies.Provides SST and English knowledge also unlike other institutes. Teachers are co operative and friendly online tests andPPT develope practical knowledge also.
Aman Kumar Shrivastava
10thMy experience with Abhyas academy is very nice or it can be said wonderful. I have been studying here from seven class. I have been completing my journey of three years. I am tinking that I should join Abhyas Academy in tenth class as I am seeing much improvement in Maths and English
Hridey Preet
9thAbhyas is an institute of high repute. Yogansh has taken admission last year. It creates abilities in child to prepare for competitive exams. Students are motivated by living prizes on basis of performance in Abhyas exams. He is satisfied with institute.
Yogansh Nyasi
7thAbout Abhyas metholodology the teachers are very nice and hardworking toward students.The Centre Head Mrs Anu Sethi is also a brilliant teacher.Abhyas has taught me how to overcome problems and has always taken my doubts and suppoeted me.
Shreya Shrivastava
8thAbhyas institute is one of the best coaching institute in the vicinity of Ambala cantt.The institute provides good and quality education to the students.The teachers are well experienced and are very helpful in solving the problems. The major advantages of the institute is extra classes for weak...
Shreya Shrivastava
8thThe experience was nice. I studied here for three years and saw a tremendous change in myself. I started liking subjects like English and SST which earlier I ran from. Extra knowledge gave me confidence to overcome competitive exams. One of the best institutes for secondary education.
Aman Kumar Shrivastava
10thAbhyas is good institution and a innovative institute also. It is a good platform of beginners.Due to Abhyas,he has got knoweledge about reasoning and confidence.My son has improved his vocabulary because of Abhyas.Teacher have very friendly atmosphere also.
Manish Kumar
10thIt was good as the experience because as we had come here we had been improved in a such envirnment created here.Extra is taught which is beneficial for future.
