GkSeries.com

NCERT Solutions for class 12 Physics | Chapter 1 - Electric Charges and Fields

Download PDF

Free download in PDF Class 12 Physics Chapter 1 Electric Charges and Fields Multiple Choice Questions and Answers for Board, JEE, NEET, AIIMS, JIPMER, IIT-JEE, AIEE and other competitive exams. MCQ Questions for Class 12 Physics with Answers were prepared based on the latest exam pattern. These short solved questions or quizzes are provided by Gkseries. These will help the students for preparation of their examination./p>

Go To Download Page
(1) 1 V equals to:
[A] 1 J
[B] 1 JC-1
[C] 1 CJ-1
[D] 1 JC
Answer: 1 JC-1
(2) When a dipole of moment
[A]
[B]
[C]
[D]
Answer:

DOWNLOAD CURRENT AFFAIRS PDF FROM APP

(3) A semicircular arc of radius r is charged uniformly and the charge per unit length is λ. The electric field at the centre is:
[A]
[B]
[C]
[D]
Answer:
(4) Four charges are arranged at the comers of a square ABCD, as shown. The force on the charge kept at the centre O is

[A] zero
[B] along the diagonal AC
[C] along the diagonal BD
[D] perpendicular to side AB
Answer: along the diagonal BD
(5) Which of the following statements is not true about Gauss’s law?
[A] Gauss’s law is true for any closed surface.
[B] The term q on the right side side of Gauss’s law includes the sum of all charges enclosed by the surface.
[C] Gauss’s law is not much useful in calculating electrostatic field when the system has some symmetry.
[D] Gauss’s law is based on the inverse square dependence on distance contained in the coulomb’s law
Answer: Gauss’s law is not much useful in calculating electrostatic field when the system has some symmetry.
(6) Gauss’s law will be invalid if
[A] there is magnetic monopoles.
[B] the inverse square law is not exactly true.
[C] the velocity of light is not a universal constant.
[D] none of these.
Answer: the inverse square law is not exactly true.
(7) A point charge +q is placed at a distance d from an isolated conducting plane. The field at a point P on the other side of the plane is
[A] directed perpendicular to the plane and away from the plane.
[B] directed perpendicular to the plane but towards the plane.
[C] directed radially away from the point charge.
[D] directed radially towards the point charge.
Answer: directed perpendicular to the plane and away from the plane.
(8) Which of the following statement is correct? The electric field at a point is [NCERT Exemplar]
[A] always continuous.
[B] continuous if there is a charge at that point.
[C] discontinuous only if there is a negative charge at that point.
[D] discontinuous if there is a charge at that point.
Answer: discontinuous if there is a charge at that point.
(9) In Fig. (i) two positive charges q2 and q3 fixed along the y-axis, exert a net electric force in the +x direction on a charge q1 fixed along the x-axis. If a positive charge Q is added at (x, 0) in figure (ii), the force on q1 is

[A] shall increase along the positive x-axis.
[B] shall decrease along the positive x-axis.
[C] shall point along the negative x-axis.
[D] shall increase but the direction changes because of the intersection of Q with q2 and qy
Answer: shall increase along the positive x-axis.
(10) The magnitude of electric field intensity E is such that, an electron placed in it would experience an electrical force equal to its weight is given by
[A] mge
[B] mg/e
[C] e/mg
[D] e²g/m²
Answer: mg/e
(11) A point charge q is placed at a distance a/2 directly above the centre of a square of side a. The electric flux through the square is
[A]
[B]
[C]
[D]
Answer:
(12) The electric field intensity due to an infinite cylinder of radius R and having charge q per unit length at a distance rir r(r > R) from its axis is
[A] directly proportional to r².
[B] directly proportional to r3.
[C] inversely proportional to r.
[D] inversely proportional to r².
Answer: inversely proportional to r.
(13) Total electric flux coming out of a unit positive charge kept in air is
[A] ε0
[B]
[C] (4πε0)-1
[D] 4πε0
Answer:
(14) An electric charge q is placed at the centre of a cube of side a. The electric flux on one of its faces will be
[A]
[B]
[C]
[D]
Answer:
(15) Electric field at a point varies as r° for
[A] an electric dipole
[B] a point charge
[C] a plane infinite sheet of charge
[D] a line charge of infinite length
Answer: a plane infinite sheet of charge
(16) A cylinder of radius R and length L is placed in a uniform electric field E parallel to the cylinder axis. The total flux for the surface of the cylinder is given by
[A]
[B]
[C]
[D] Zero
Answer: Zero
(17) The electric field inside a spherical shell of uniform surface charge density is
[A] zero.
[B] constant, less than zero.
[C] directly proportional to the distance from the centre.
[D] none of the these
Answer: zero.
(18) Two charges of equal magnitudes kept at a distance r exert a force F on each other. If the charges are halved and distance between them is doubled, then the new force acting on each charge is
[A] F/8
[B] F/4
[C] 4F
[D] F/16
Answer: F/16
(19) A charge Q is divided into two parts of q and Q – q. If the coulomb repulsion between them when they are separated is to be maximum, the ratio of Q/q should be
[A] 2:1
[B] 1/2
[C] 4:1
[D] 1/4
Answer: 2:1
(20) 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
[A] zero having no direction.
[B] 8F towards +Q charge.
[C] 8F towards -Q charge.
[D] 4F towards +Q charge.
Answer: 8F towards -Q charge.

Please share this page

Chapters

Click Here to Read more questions

Teacher Eligibility Test