Two identical point charges of magnitude –q are fixed as shown in the figure below. A third charge +q is placed midway between the two charges at the point P. Suppose this charge +q is displaced a small distance from the point P in the directions indicated by the arrows, in which direction(s) will +q be stable with respect to the displacement?

(a)

A₁ and A₂

(b)

B₁ and B₂

(c)

both directions

(d)

No stable

Which charge configuration produces a uniform electric field?

(a)

point charge

(b)

uniformly charged infinite line

(c)

uniformly charged infinite plane

(d)

uniformly charged spherical shell

If voltage applied on a capacitor is increased from V to 2V, choose the correct conclusion.

(a)

Q remains the same, C is doubled

(b)

Q is doubled, C doubled

(c)

C remains same, Q doubled

(d)

Both Q and C remain same

Two metallic spheres of radii 1 cm and 3 cm are given charges of -1 \(\times\) 10^-2 C and 5 \(\times\) 10^-2 C respectively. If these are connected by a conducting wire, the final charge on the bigger sphere is

(a)

3 \(\times\) 10^-2 C

(b)

4 \(\times\) 10^-2 C

(c)

1 \(\times\) 10^-2 C

(d)

2 \(\times\) 10^-2 C

The value of constant 'K' in coulomb law is _____________.

(a)

0.9 x 10⁹ Nm² C²

(b)

9 x 10^-9 Nm²C²

(c)

9 x 10⁹ Nm^-2 C^-2

(d)

9 x 10⁹ Nm² C^-2

The relative permittivity of water is _______.

(a)

ε_r = 70

(b)

ε_r = 75

(c)

ε_r = 80

(d)

ε_r = 85

Which one of these is a vector quantity?

(a)

Electric charge

(b)

Electric field

(c)

Electric flux

(d)

Electric potential

The electric field created by a _________ is basically a non-uniform electric field.

(a)

Test charge

(b)

Positive charge

(c)

Negative charge

(d)

Point charge

Two condensers (capacitors) of capacity C₁ and C₂ are connected in parallel. A charge Q given to then is shared. The ratio of the charges Q is _________

(a)

\(\frac { { C }_{ 2 } }{ { C }_{ 1 } } \)

(b)

\(\frac { { C }_{ 1 } }{ { C }_{ 2 } } \)

(c)

C₁.C₂

(d)

\(\frac { 1 }{ { C }_{ 1 }\times { C }_{ 2 } } \)

Increasing the charge on the plates of a capacitor means ___________

(a)

increasing the capacitance

(b)

increasing the potential difference between the plates

(c)

both (a) and (b) above

(d)

none of the above

An electric dipole placed at an angle in a nonuniform electric field experiences

(a)

neither a force nor a torque

(b)

torque

(c)

both force and torque

(d)

force only

Two copper spheres A and B of same size are charged to same potential. A is hollow and B is solid. Which of the two holds more charge?

(a)

Solid sphere cannot hold any charge

(b)

hollow sphere cannot hold any charge

(c)

both have zero charge

(d)

both have the same charge

A charge q is placed at the centre of a cubical box of side with top open. The flux of electric field through the surface of the cubical box is

(a)

Zero

(b)

\(\frac { q }{ { \varepsilon }_{ 0 } } \)

(c)

\(\frac { q }{ 6{ \varepsilon }_{ 0 } } \)

(d)

\(\\ \frac { 5q }{ 6{ \varepsilon }_{ 0 } } \)

The electric flux over a sphere of radius 1m is ф. If radius of the sphere were doubled without changing the charge enclosed, electric flux would become

(a)

2ф

(b)

\(\\ \\ \\ \frac { \phi }{ 2 } \)

(c)

\(\\ \\ \\ \frac { \phi }{ 4 } \)

(d)

ф

For continuous charge distributions, _____ methods can be used.

(a)

integration

(b)

differentiation

(c)

multiplication

(d)

addition

Electrostatic force is stroger than gravitational force by_________.

(a)

2.23 x 10³⁹ times

(b)

2.25 x 10³⁹ times

(c)

2.27 x 10³⁹ times

(d)

2.29 x 10³⁹ times

Which of the following is a scalar quantity?

(a)

electric dipole moment

(b)

electric field intensity

(c)

electric potential

(d)

current density

The force between two charges at a particular distance in air is 36 N. If the distance between the charges is filled by a medium of dielectric constant 6, then the force is:

(a)

216 N

(b)

6 N

(c)

30 N

(d)

24 N

The value of relative permittivity of air is

(a)

8.854 x 10^-12C²N^-1m^-2

(b)

9 x 10⁹ C² N^-1m^-2

(c)

1

(d)

8.854 x 10¹²

By using law of conservation of electric charge balance the following equations:
₉₂U²³⁸ ⇾ ₉₀Th²³⁴ +________.

(a)

₂He⁴

(b)

₁H³

(c)

₁H²

(d)

₁H¹

Electric field intensity and electric potential are related by_________.

(a)

E = -\(\frac{dV}{dt}\)

(b)

E = -\(\frac{dV}{dx}\)

(c)

E = \(\frac{dV}{dt}\)

(d)

E = \(\frac{-dx}{dV}\)

Near a charged object A another earthed object B is placed. Charges are induced on B. If B is removed. After that the charge on A ________.

(a)

remains the same

(b)

decreases

(c)

increases

(d)

becomes zero

When an electric dipole is placed in a uniform external electric field parallel to the field, it will experience_________.

(a)

a torque but no force

(b)

a force but no torque

(c)

a torque as well as a force

(d)

neither a force nor a torque