List of top Physics Questions

A capacitor of capacity $C_1$ is charged by connecting it across a battery of e.m.f. $V_0$. The battery is then removed and the capacitor is connected in parallel with an uncharged capacitor of capacity $C_2$.The potential difference across this combination is
A certain charge $Q$ is divided at first into two parts, $q$ and $Q - q$. Later on the charges are placed at a certain distance. If the force of interaction between two charges is maximum, then $Q/q$ =
A charged oil drop of mass $2.5 \times 10^{-7}$ kg is in space between the two piates, each of area $2 \times 10^{-2} \, m^2$ of a parallel piate capacitor. When the upper plate has a charge of $5 \times 10^{-7} \, C$ and the lower plate has an equal negative charge, the oil remains stationary. The charge of the oil drop is (Take g = $10 \, m/s^2$ )
A large solid sphere with uniformly distributed positive charge has a smooth narrow tunnel through its centre. A small particle with negative charge, initially at rest far from the sphere, approaches it along the line of the tunnel, reaches its surface with a speed $v$, and passes through the tunnel. Its speed at the centre of the sphere will be
A conducting spherical shell of inner radius $2R$ and outer radius $3R$ has a positive point charge $q$ located at its centre. What is the electric potential at point $P$, which is at a distance $\frac{6}{7}R$ from its centre as shown in the figure.
In the circuit shown in figure, $C = 6 \,\mu F$. The charge stored in the capacitor of capacity $C$ is
A cube of side b has charge q at each of its vertices. The electric field at the center of the cube will be
A cylinder of radius $r$ and length $l$ is placed in a uniform electric field $E$ parallel to the axis of the cylinder. What is the total electric flux through the surface of the cylinder ?
A cylindrical capacitor has two co-axial cylinders of length $20 \,cm$ and radii $1.5\, cm$ and $1.6 \,cm$. The outer cylinder is earthed and inner cylinder is given a charge of $4\, \mu C$. The capacitance of the system is (neglect end effects)
In the arrangement of capacitors shown in figure, each capacitor is of $9 \,\mu F$, then the equivalent capacitance between the points $A$ and $B$ is
A hollow metallic surface of radius $10\, cm$ is given a charge of $3.2\times10^{-19}$ coulomb. The electric potential at a point $4\,cm$ from the centre is
A metallic sphere of radius $18 \,cm$ has been given a charge of $5 \times 10^{-6} \, C$ The energy of the charged conductor is
A one coulomb charge is placed on an insulated stand at the centre of a spherical conductor of radius $1\,m$. The sphere is given a charge of $1\,C$. The electrostatic force experienced by the charge at the centre will be :
A parallel plate capacitor has a capacitance of $50\,\mu F$ in air and $100\,\mu F$ when immersed in an oil. The dielectric constant of the oil is
A parallel plate capacitor is charged by connecting to a battery. After charging, the battery is disconnected. Which of the following increases, when the plates of the capacitor are moved apart ?
A parallel plate capacitor is connected to a battery as shown in figure. Consider two situations
(i) key $K$ is kept closed and plates of capacitors are moved apart using insulating handle (ii) key $K$ is opened and plates of capacitors are moved apart using insulating handle Which of the following statements is correct?
A parallel plate capacitor with air between the plates has a capacitance of $10\, pF$. The capacitance, if the distance between the plates is reduced by half and the space between them is filled with a substance of dielectric constant $4$ is
A soap bubble is charged to a potential of $16\,V$. Its radius is then doubled. The potential of the bubble now will be :
A soap bubble is given a negative charge, then its radius
A spherical capacitor consists of two concentric spherical conductors, held in position by suitable insulating supports as shown in figure.
The capacitance $C$, of this spherical capacitor is
A test charge $q_0$ is released from rest at a distance $r$ from a source charge $q$. What will be the maximum value of the kinetic energy that may be acquired by the test charge ?
Ah electron enters an electric field with its velocity in the direction of the electric lines of force. Then
An electric dipole is along a uniform electric field: If it is deflected by $60^\circ$, work done by an agent is $2 \times 10^{-19}$ Then the work done by an agent if it is deflected by $30^0$ further is
An electric dipole of length $20 \,cm$ having $\pm 3 \times10^{-3}\,C$ charge placed at $60^{\circ}$ with respect to a uniform electric field experiences a torque of magnitude $6\, N\, m$. The potential energy of the dipole is
An electric dipole when placed in a uniform electric field will have minimum potential energy,if the angle between dipole moment and electric field is