The inner and outer radii of a coaxial cable are 0.1 mm and 0.6 mm respectivley.If the core material has dielectric constant 12, calculate the capacitance per metre of the cable.

The radii of curvature of the two faces of a convex lens are 0.1 m and 0.15 m respectively.If the foal length of the lens is 0.12 m,find the refractie index of the material of the lens.

A spherical capacitor has an outer sphere of radius 0.15m and the inner sphere of diameter 0.2m The outer sphere is earthed and the inner shere is given charge of 6 muC. The space between the concentric spheres is filled with a material of dielectric constant 6. Calculate capacitacne and potential of inner sphere.

A spherical capacitor has an inner sphere of radius 12 cm and an outer sphere of radius 13 cm. The outer sphere is earthed and the inner sphere is given a charge of 2.5 muC . The space between the concentric spheres is filled with a liquid of dielectric constant 32. Determine the capacitance of the capacitor.

The core of toroid having 3,000 turns has inner and outer radii of 11 cm and 12 cm respectively. The magnetic field in the core for a current of 0.70 A is 2.5 T. What is the relative permeability of the core?

A spherical capacitor has an inner sphere of radius 12 cm and an outer sphere of radius 13 cm. The outer sphere is earthed and the inner sphere is given a charge of 2.5 muC . The space between the concentric spheres is filled with a liquid of dielectric constant 32. Compare the capacitance of this capacitor with that of an isolated sphere of radius 12 cm. Explain why the latter is much smaller.

Two parallel plate capacitors A and B have the same separation d= 8.85xx10^-4m between the plates. The plate area of A and B are 0.04m^2 and 0.02m^2 respectively. A slab of dielectric constant (relative permittivity) K=9 has dimensions such that it can exactly fill the space between the plates of capacitor B. A is then charged to a potential difference of 110V. Calculate the capacitance of A and the energy stored in it.

A cable consisting of a wire 3 mm in diameter and insulated with 3 mm thick dielectric of relative permittivity 4.5 is placed in water. Calculate the capacitance of 1 km length of the cable.

A parallel plate capacitor has two plates of sides 0.055 m and 0.04 m of air. Their distance apart is 0.7 mm. The dielectric constant of the medium in between is 4. Find the capacitance of the capacitor.

A parallel plate capacitor with air between the plates has capacitance of 9pF. The separation between its plates is 'd'. The space between the plates is now filled with two dielectrics. One of the dielectrics has dielectric constant k_1=3 and thickness d/3 while the other one has dielectric constant k_2=6 and thickness (2d)/(3) . Capacitance of the capacitor is now

A spherical capacitor has an inner sphere of radius 12 cm and an outer sphere of radius 13 cm. The outer sphere is earthed and the inner sphere is given a charge of 2.5 muC . The space between the concentric spheres is filled with a liquid of dielectric constant 32. What is the potential of the inner sphere?