A spherical shell of radius b with charge Q is expanded to a radius a. Find the work done by the electrical forces in the process.

A drop of mercury of radius 0.2 cm is broken into 8 droplets of the same size. Find the work done if the surface tension of mercury is 435.5 dyne/cm.

A drop of mercury of radius 0.2 cm is broken into 8 droplets of the same size. Find the work done if the surface tensions of mercury is 435.5 dyne/cm

A small sphere of radius r_1 and charge q_1 is enclosed by a spherical shell of radius r_2 and charge q_2 Show that if q_1 is positive, charge will necessary flow from the sphere to the shell (when the two are connected by a wire) no matter what the charge q_2 on the shell is.

A spherical liquid drop of radius R is divided into eight equal droplets . If surface tension is T, then the work done in this process will be

Assertion : the net work done by an electrostatic field on a charge whilr moving it from one point to another is independent of path. Reason: the net work done by an electrostatic force on a charge in it moving along a closed loop is zero.

A spherical soap bubble is expanding so that its radius is increasing at the rate of 0.02 cm/sec. At what rate is the surface area is increasing, when its radius is 5cm?

A charged spherical conductor of radius R carries a charge + Q. A point test charge + q_0 is placed at a distance x from the surface of the sphere. The force experienced by the test change will be proportional to

Charges Q are placed at the ends of a diagonal of a square and charges q are placed at the other two corners. The conditions for the net electric force on Q to be zero is