English
Karnataka Board PUCPUC Science Class 11

The Electric Field and the Electric Potential at a Point Are E and V, Respectively.

Advertisements
Advertisements

Question

The electric field and the electric potential at a point are E and V, respectively.  

Options

  •  If E = 0, V must be zero. 

  •  If V = 0, E must be zero. 

  • If E ≠ 0, V cannot be zero. 

  • If V ≠0, E cannot be zero. 

  • None of the above.

MCQ
Advertisements

Solution

None of the above.

Electric field, \[E = \frac{- dV}{dr}\] where V = electric potential
For E = 0,  V should be constant. 
So, when E = 0,  it is not necessary that V should be 0.
Hence, none of the above signifies the correct relation.

 

shaalaa.com
  Is there an error in this question or solution?
Chapter 29: Electric Field and Potential - MCQ [Page 120]

APPEARS IN

HC Verma Concepts of Physics Volume 1 and 2 [English]
Chapter 29 Electric Field and Potential
MCQ | Q 3 | Page 120

RELATED QUESTIONS

In some old texts it is mentioned that 4π lines of force originate from each unit positive charge. Comment on the statement in view of the fact that 4π is not an integer. 


Electric potential decreases uniformly from 120 V to 80 V, as one moves on the x-axis from x = −1 cm to x = +1 cm. The electric field at the origin 

(a) must be equal to 20 Vcm−1
(b) may be equal to 20 Vcm−1
(c) may be greater than 20 Vcm−1
(d) may be less than 20 Vcm−1 


A 10-cm long rod carries a charge of +50 μC distributed uniformly along its length. Find the magnitude of the electric field at a point 10 cm from both ends of the rod.


Consider a uniformly charged ring of radius R. Find the point on the axis where the electric field is maximum.

 

A particle of mass 1 g and charge 2.5 × 10−4 C is released from rest in an electric field of 1.2 × 10 4 N C−1.   How long will it take for the particle to travel a distance of 40 cm?


A ball of mass 100 g and with a charge of 4.9 × 10−5 C is released from rest in a region where a horizontal electric field of 2.0 × 104 N C−1 exists. (a) Find the resultant force acting on the ball. (b) What will be the path of the ball? (c) Where will the ball be at the end of 2 s?


An electric field of 20 NC−1 exists along the x-axis in space. Calculate the potential difference VB − VA where the points A and B are
(a) A = (0, 0); B = (4 m, 2m)
(b) A = (4 m, 2 m); B = (6 m, 5 m)
(c) A = (0, 0); B = (6 m, 5 m)
Do you find any relation between the answers of parts (a), (b) and (c)?  


Consider the situation of the previous problem. A charge of −2.0 × 10−4 C is moved from point A to point B. Find the change in electrical potential energy UB − UA for the cases (a), (b) and (c). 


The electric potential existing in space is \[\hspace{0.167em} V(x,   y,   z) = A(xy + yz + zx) .\] (a) Write the dimensional formula of A. (b) Find the expression for the electric field. (c) If A is 10 SI units, find the magnitude of the electric field at (1 m, 1 m, 1 m).


Assume that each atom in a copper wire contributes one free electron. Estimate the number of free electrons in a copper wire of mass 6.4 g (take the atomic weight of copper to be 64 g mol−1). 


Which of the following methods can be used to charge a metal sphere positively without touching it? Select the most appropriate.


Electric lines of force about a negative point charge are ______.

Consider a region inside which, there are various types of charges but the total charge is zero. At points outside the region ______. 


In general, metallic ropes are suspended on the carriers taking inflammable materials. The reason is ______.


Two similar spheres having +Q and -Q charges are kept at a certain distance. F force acts between the two. If at the middle of two spheres, another similar sphere having +Q charge is kept, then it experiences a force in magnitude and direction as ______.


The Electric field at a point is ______.

  1. always continuous.
  2. continuous if there is no charge at that point.
  3. discontinuous only if there is a negative charge at that point.
  4. discontinuous if there is a charge at that point.

Five charges, q each are placed at the corners of a regular pentagon of side ‘a’ (Figure).

(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 corners (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 corners?


What does the symbol \[\hat{\mathbf{r}}_{iP}\] represent in the electric field formula?


What is the value and unit of Coulomb's constant \[\frac{1}{4\pi\varepsilon_0}\]?


In the electric field formula, what does the symbol \[\hat r_i\]P represent?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×