Two identical charged spheres are suspended by strings of equal lengths. The strings make an angle `30^@` with each other. When suspended in a liquid of density `800 kg m^-3`, the angle remains the same. Wahat is the dielectric constant of the liquid? The density of the material of the sphere is 1600 kg `m^-3`

Two charge spheres separated at a distance d exert a force F on each other. If they are immersed in a liquid of dielectric constant K=2, then the force (if all conditions are same) is

Two similar small metallic spheres are suspended by eal threads from the same point. When either sphere is given a similar charge of 36 statC. The distance between them is 6 cm. If the length of each thread is 5 cm, find the mass of each sphere and the tension in each thread.

A wire having a mass of 0.45 kg posseses a resistanfce of 0.014 Omega . If the resistivity of the material fo wire is 1.78 xx10^-7 Omegam , calculate its length and radius. Given that the density of the material of wire is 8.93 xx10^3 kg m^-3

Two small spheres each of mass 10 mg are suspended from a poimt by threads 0.5 m long. They are equally charged and repel each other to a distance of 0.28 m. If g = 10 ms^-2 , what is the charge on each ?

Calculate the capacitance of a spherical capacitor if the diameter of inner sphere is 0.2m and that of the outer sphere is 0.3m, the space between them being filled with a liquid having dielectric constant 20

A steel wire of mass mu per unit length with a circular cross section has a radius of 0.1 cm. The wire is of length 10 m when measured lying horizontal, and hangs from a hook on the wall. A mass of 25 kg is hung from the free end of the wire. Assuming the wire to be uniform and lateral strains < < longitudinal strains, find the extension in the length of the wire. The density of steel is 7860 kg m^-3 (Young's modulues Y = 2 xx 10^11 N m^-2)

An electric dipole of length 4 cm, when placed with its axis making an angle of 60^@ with a uniform eletric field experiences a torque of 4sqrt3 N m. Calculate the potential energy of the dipole, if the dipole has charges of +- 8 nC .