1.	When a glass rod is rubbed with silk, it ?
	gives protons to silk.
	gains protons from silk.
	gives electrons to silk.
	gains electrons from silk.
	Answer: gives electrons to silk. Explanation: On rubbing a glass rod with silk, excess electrons are transferred from glass to silk. So glass rod becomes positive and silk becomes negative.
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2.	The electric field inside a spherical shell of uniform surface charge density is ?
	directly proportional to the distance from the centre.
	constant, less than zero.
	zero.
	none of the these
	Answer: zero. Explanation: All charges reside on the outer surface of the shell so according to Gauss’s law, electric field inside the shell is zero.
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3.	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 ?
	directed radially away from the point charge
	directed radially towards the point charge
	directed perpendicular to the plane but towards the plane
	directed perpendicular to the plane and away from the plane
	Answer: directed perpendicular to the plane and away from the plane Explanation: When a point charge +q is placed at a distance d from an isolated conducting plane, some negative charge develops on the surface of the plane towards the charge and an equal positive charge develops on opposite side of the plane. Hence, the field at a point P on the other side of the plane is directed perpendicular to the plane and away from the plane
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4.	Coulomb’s law is true for ?
	charged as well as uncharged particles
	nuclear distances (= 10^-15 m)
	atomic distances (= 10^-11 m)
	all the distances
	Answer: all the distances Explanation: Coulomb's law is true for all distances whether it is small and large. Hence it is called a long range force.
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5.	If an electron has an initial velocity in a direction different from that of an electric field, the path of the electron is ?
	a parabola
	a circle
	a straight line
	an ellipse
	Answer: a parabola Explanation: The path is a parabola, because initial velocity can be resolved into two rectangular components, one along E and other perpendicular to E. The former decreases at a constant rate and latter is unaffected. The resultant path is therefore a parabola.
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6.	Electric flux over a surface in an electric field may be ?
	negative
	zero
	positive
	All of the above
	Answer: All of the above Explanation: Apply Gauss's law, the electric flux ,?=?Eds= Qen/ where Qen charge enclosed by the surface. If charge Qen is positive, the flux is positive. If charge Qen is negative, the flux is negative. If charge Qen is zero, the flux is zero.
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7.	An electric dipole is kept in a non-uniform electric field. It experiences ?
	a force but not a torque
	neither a force nor a torque
	a force and a torque
	a torque but no force
	Answer: a force and a torque Explanation: When a dipole is placed in an electric field, the opposite charges on the dipole both experience a force due to the electric field. This force is given by the product of the charge and the electric field and the direction of the force for both the charges will be opposite to one another. Now since the electric field is non-uniform, so the force experienced by both the charges will be unequal. Hence there will be net force acting on the dipole as they won’t cancel out each other. Now since the forces on the charges are not linear so the dipole will also experience a non-zero torque. Hence the dipole will experience both force and torque when placed in a non uniform electric field.
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8.	Quantisation of charge implies ?
	There is a minimum permissible magnitude of charge
	Charge can’t be created
	Charge exists on particles
	Charge does not exist
	Answer: There is a minimum permissible magnitude of charge Explanation: There is a minimum permissible magnitude of charge According to the concept of quantisation of charge, electric charge can exist only as an integral multiple of charge of an electron. The charge of an electron is considered as the basis of any charge system. That is q=ne , where n is an integer and e is the charge of an electron. It is not possible to have a charge less than the charge of an electron to any system. i.e. It is the minimum charge of any system. There is a minimum permissible magnitude of charge.
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9.	If an electric dipole is kept in a uniform electric field then resultant electric force on it is ?
	depend upon capacity of dipole
	never zero
	always zero
	None
	Answer: always zero Explanation: Even if we change the orientation, the length and the charge of the dipole, the net force on the dipole will be equal to zero. Hence, the electric force on a dipole when it is placed in a uniform electric field is always zero.
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10.	Two point charges +8q and -2q are located at ,v = O and ,v = L respectively. The location of a point on the .v-axis at which the net electric field due to these two point charges b is zero ?
	2L
	8L
	4L
	L/4
	Answer: 2L Explanation:
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