Five charges,q each are placed at the comers of a regular pentagon of side a.

i) What will be the electric field at O, the centre of the pentagon?
(ii) What will be the electric field at O if the charge from one of the comers (say A) is removed?
(iii) What will be the electric field at O if the charge q at A is replaced by – q?
(b) How would your answer to (a) be affected if pentagon is replaced by n-sided regular polygon with charge q at each of its comers?
Five charges,q each are placed at the comers of a regular pentagon of side a.
i) What will be the electric field at O, the centre of the pentagon?
(ii) What will be the electric field at O if the charge from one of the comers (say A) is removed?
(iii) What will be the electric field at O if the charge q at A is replaced by – q?
(b) How would your answer to (a) be affected if pentagon is replaced by n-sided regular polygon with charge q at each of its comers?
-
1 Answer
-
This is a Long Answer Type Questions as classified in NCERT Exemplar
Explanation- (a)
(i) The electric field at the center of pentagon is zero because the distance from the center is same.
(ii) The field through one charge is Kq/r2
(iii) When one charge is positive and other is negative then net force towards negative charge. So net force is Kq/r2+ Kq/r2= 2Kq/r2
(b) It doesn't depend upon the number of sides increasing the net electric field is zero.
Similar Questions for you
The following are the topics covered in this chapter: Electric Field and Field Lines, Gauss's Law, Electric Dipole, Conductors and Insulators, and Electric Flux.
Indeed, it is an easy chapter of Class 12 Physics. In this chapter, you will learn about the foundational concepts like Gauss's law and electric fields.
Flux through the 6 sides of square (i.e. cube)
Flux through a square
In the medical entrance test NEET, this chapter has a moderate weightage. You can expect around 2-3 questions of this chapter that contributes to the 3-5% of the total marks in the Physics section.
Taking an Exam? Selecting a College?
Get authentic answers from experts, students and alumni that you won't find anywhere else
Sign Up on ShikshaOn Shiksha, get access to
- 65k Colleges
- 1.2k Exams
- 688k Reviews
- 1800k Answers