271.

Three capacitors 3 µF, 6 µF and 6 µF are connected in series to a source of 120 V. The potential difference, in volt, across the 3 µF capacitor will be

• 24

• 30

• 40

• 60

A parallel plate capacitor is charged and then disconnected from the charging battery. If the plates are now moved farther apart by pulling at them by means of insulating handles, then

• the energy stored in the capacitor decreases

• the capacitance of the capacitor increases

• the charge on the capacitor decreases

• the voltage across the capacitor increases

Half of the space between the plates of a parallel-plate capacitor is filled with a dielectric material of dielectric constant K. The remaining half contains air as shown in the figure. The capacitor is now given a charge Q. Then

• electric field in the dielectric-filled region is higher than that in the air-filled region.

• on the two halves of the bottom plate the charge densities are unequal.

• charge on the half of the top plate above the air-filled pant is $\frac{\mathrm{Q}}{\mathrm{K} + 1}$

• capacitance of the capacitor shown above is $\left(1 + \mathrm{K}\right) \frac{{\mathrm{C}}_0}{2}$, where C₀ is the capacitance of the same capacitor with the dielectric removed.

A 5 µF capacitor is connected in series with a 10 µF capacitor. When a 300 V potential difference is applied across this combination, the total energy stored in the capacitors is

• 15 J

• 1.5 J

• 0.15 J

• 0.10 J