MCQ
A parallel plate capacitor has a capacity C. The separation between the plates is doubled and a dielectric medium is introduced between the plates. If the capacity now becomes 2C, the dielectric constant of the medium is
  • A
    2
  • B
    1
  • 4
  • D
    8

Answer

Correct option: C.
4
4

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

If the path difference between the slits $S_1$ and $S_2$ is $\lambda$, the central fringe will have an intensity of:
Two wires each carrying a steady current $I$ are shown in four configurations in Column $I$. Some of the resulting effects are described in Column $II$. Match the statements in Column $I$ with the statements in Column $II$ and indicate your answer by darkening appropriate bubbles in the $4 \times 4$ matrix given in the $ORS$.

Column $I$ Column $II$
$(A)$ Point $P$ is situated midway between the wires. $Image$ $(p)$ The magnetic fields $(B)$ at $P$ due to the currents in the wires are in the same direction.
$(B)$ Point $P$ is situated at the mid-point of the line joining the centers of the circular wires, which have same radii. $Image$ $(q)$ The magnetic fields $(B)$ at $P$ due to the currents in the wires are in opposite directions.
$(C)$ Point $P$ is situated at the mid-point of the line joining the centers of the circular wires, which have same radii. $Image$ $(r)$ There is no magnetic field at $P$.
$(D)$ Point $P$ is situated at the common center of the wires. $Image$ $(s)$ The wires repel each other.

 

The resonance point in ${X_L} - f$ and ${X_C} - f$ curves is
A half ring of radius $R$ has a charge of $\lambda$ per unit length. The electric force on $1\, C$ charged placed at the centre is
A proton, a deuteron and an α particle are accelerated through same potential difference and then they enter in a normal uniform magnetic field, the ratio of their kinetic energies will be:
The nucleus ${92^U}^{234}$ splits exactly in half in a fission reaction in which two neutrons are released. The resultant nuclei are
A conductor behaves as a superconductor
The refractive index of water with respect to air is 4 / 3 and the refractive index of glass with respect to air is 3/2. The refractive index of water with respect to glass is
$A$ conducting ring of radius a is rotated about a point $O$ on its periphery as shown in the figure in a plane perpendicular to uniform magnetic field $B$ which exists everywhere. The rotational velocity is $\omega .$ Choose the correct statement $(s)$ related to the potential of the points $P, Q$ and $R$
The energy that should be added to an electron to reduce its de Broglie wavelength from one nm to 0.5 nm is