Two long straight conducors are placed parallel at a distance of 2 cm form each other. When one of them caries a current of 60 A, the force on 1 m length of the other is 1,200 dyne. Calculate current in the other.

Two long parallel wires are at a distance of 1 m. Both of them carry 1A of current. The force of attraction per unit length between the two wires is

Two equal charges placed in air and separated by a distance of 2 m repel each other with a force of 10^-4 N. Calculate the magnitude of either of the charges.

Two equal charges placed in air separated by a distance 3 m repel each other with force 0.1 g f. Calculate the magnitude of either of the charges.

Two circular conductors are perpendicular to each other as shown in the figure.If current in any one is changed, will there be induced current in the other ?

Two parallel wires in free spaces are 10cm apart and each carries a current of 10A in the same direction. The force one wire exerts on the other per metre of length is

If n straight lines in a plane are such that no two of them are parallel and no three of them are concurrent, prove that they intersect each other in (n(n-1))/2 points.

The force between two equal charges placed in a medium at a distance of 9 cm from each other is 16 dyne. On increasing one of the charges by 56 statC, it is found that the distance between the charges must be changed by 3 cm in order to keep the force between them the same Calculate the magnitude of the charges and the dielectric constant of the medium . Given : 1 C = 3 xx 10^9 statC .

Two long parallel straight wires X and Y separated by a distance of 5 cm in air carry current of 10 A and 5 A respectively in opposite directions. Calculate the magnetic force and direction of the force on a 20 cm length of the wire Y.

A convex and concave lens having focal lengths of 30 cm and j10 cm respectively are placed at a distance 20 cm from each other.Whre should a source of light be placed so that the system of the two lenses will produce a beam of parallel rays?