Equal charges q are placed at the four corners A, B, C, D of a square of length a. The magnitude of the force on the charge at B will be  (1) $\frac{3{q}^{2}}{4\pi {\epsilon }_{0}{a}^{2}}$ (2) $\frac{4{q}^{2}}{4\pi {\epsilon }_{0}{a}^{2}}$ (3) $\left(\frac{1+2\sqrt{2}}{2}\right)\frac{{q}^{2}}{4\pi {\epsilon }_{0}{a}^{2}}$ (4) $\left(2+\frac{1}{\sqrt{2}}\right)\frac{{q}^{2}}{4\pi {\epsilon }_{0}{a}^{2}}$

Subtopic:  Coulomb's Law |
69%
From NCERT
PMT - 1994
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Two identical conductors of copper and aluminium are placed in an identical electric field. The magnitude of induced charge in the aluminum will be

(1) Zero

(2) Greater than in copper

(3) Equal to that in copper

(4) Less than in copper

Subtopic:  Electric Field |
From NCERT
AIIMS - 1999
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Two spherical conductors $$B$$ and $$C$$ having equal radii and carrying equal charges in them repel each other with a force $$F$$ when kept apart at some distance. A third spherical conductor having same radius as that of $$B$$ but uncharged is brought in contact with $$B$$, then brought in contact with $$C$$ and finally removed away from both. The new force of repulsion between $$B$$ and $$C$$ is:
1. $$\frac{F}{4}$$
2. $$3\frac{F}{4}$$
3. $$\frac{F}{8}$$
4. $$3\frac{F}{8}$$

Subtopic:  Coulomb's Law |
61%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Two equally charged, identical metal spheres A and B repel each other with a force 'F'. The spheres are kept fixed with a distance 'r' between them. A third identical, but uncharged sphere C is brought in contact with A and then placed at the mid-point of the line joining A and B. The magnitude of the net electric force on C is

(1) F

(2) 3F/4

(3) F/2

(4) F/4

Subtopic:  Electric Field |
55%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

An infinite number of charges, each of charge $$1$$ μC, are placed on the $$x$$-axis with co-ordinates $$x$$ = 1, 2, 4, 8, ....∞. If a charge of $$1$$ C is kept at the origin, then what is the net force acting on $$1~\text{C}$$ charge?
 1 $$9000$$ N 2 $$12000$$ N 3 $$24000$$ N 4 $$36000$$ N
Subtopic:  Coulomb's Law |
66%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A charge q is placed at the centre of the line joining two equal charges Q. The system of the three charges will be in equilibrium, if q is equal to

(1) $-\frac{Q}{2}$

(2) $-\frac{Q}{4}$

(3) $+\frac{Q}{4}$

(4) $+\frac{Q}{2}$

Subtopic:  Coulomb's Law |
67%
From NCERT
PMT - 1995
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The figure shows the electric lines of force emerging from a charged body. If the electric fields at A and B are EA and EB respectively and if the distance between A and B is r, then:

1. $$E_{A}~>~E _{B}$$
2. $$E_{A}~<~E _{B}$$
3. $$E_{A}~=~\frac{E_{B}}{r^{}}$$
4. $$E_{A}~=~\frac{E_{B}}{r^{2}}$$

Subtopic:  Electric Field |
88%
From NCERT
PMT - 1986
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

$$ABC$$ is an equilateral triangle. Charges $$+q$$  are placed at each corner. The electric intensity at $$O$$ will be:

 1 $$\dfrac{1}{4\pi\epsilon _0}\dfrac{q}{r^{2}}$$ 2 $$\dfrac{1}{4\pi\epsilon _0}\dfrac{q}{r^{}}$$ 3 zero 4 $$\dfrac{1}{4\pi\epsilon _0}\dfrac{3q}{r^{2}}$$
Subtopic:  Electric Field |
87%
From NCERT
PMT - 1985
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

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

(1) mge

(2) $\frac{mg}{e}$

(3) $\frac{e}{mg}$

(4) $\frac{{e}^{2}}{{m}^{2}}g$

Subtopic:  Electric Field |
83%
From NCERT
PMT - 1975
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A charge particle is free to move in an electric field. It will travel

(1) Always along a line of force

(2) Along a line of force, if its initial velocity is zero

(3) Along a line of force, if it has some initial velocity in the direction of an acute angle with the line of force

(4) None of the above

Subtopic:  Electric Field |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints