n identical point charges are kept symmetrically on the periphery of the circle` x^2+y^2=R^2` in xy-plane. the resultant electric field at (0,0,R) is E1 and at (0, 0, 2R) is E2. the ratio of E1/E2 is

A time varying magnetic field B=krt (where k is a constant r is the radial distance from centre O) is existing in a circular region of radius R as shown. If induced electric field at r=(R)/(2) is E_(1) and at r=2R is E_(2) then the ratio (E_(2))/(E_(1)) is

A circular ring of radius R and uniform linear charge density +lamdaC//m are kept in x - y plane with its centre at the origin. The electric field at a point (0,0,R/sqrt(2)) is

Consider two point charges q_(1)=q_(2)=q(qgt0) placed in x-y plane at (0,-R) and (R,0) as shown in the figure. Now charges q_(2) starts revolving in anticlockwise sense with uniform angular velocity omega in a circle about origin in xy-plane. E is magnitude of net field at origin, V is potential at origin and E_(x) is x-component of field at origin then select correct variation of V,E_(x) and E with time t.

The dimensions of 1/2 in_(0) E^(2) ( in_(0) : permittivity of free space, E: electric field) is-

A charge Q is placed at the centre of a square If electric field intensity due to the charge at the corners of the square is E_(1) and the intensity at the mid point of the sidde of square is E_(2) then the ratio of (E_(1))/(E_(2)) will be

Two uniformly charged solid spheres are such that E_1 is electric field at surface of 1^(st) sphere due to itself. E_2 is electric field at surface of 2^(nd) sphere due to itself. r_1, r_2 are radius of 1^(st) and 2^(nd) sphere respectively. If E_1/E_2=r_1/r_2 then ratio of potential at the surface of spheres 1^(st) and 2^(nd) due to their self charges is :

Charge Q is given a displacement r=ahati+bhatj in electric field E=E_1hati+E_2hatj . The work done is

Let E1 and E2, be two ellipses whose centers are at the origin.The major axes of E1 and E2, lie along the x-axis and the y-axis, respectively. Let S be the circle x^2 + (y-1)^2= 2 . The straight line x+ y =3 touches the curves S, E1 and E2 at P,Q and R, respectively. Suppose that PQ=PR=[2sqrt2]/3 .If e1 and e2 are the eccentricities of E1 and E2, respectively, then the correct expression(s) is(are):

Consider two charged metallic spheres S_1 and S_2 of radii R and 4R, respectively. The electric fields E_1 (on S_1 ) and E_2 (on S_2 ) on their surfaces are such that E_1/E_2 = 5/1 . Then the ratio V_1 (on S_1 ) / V_1 (on S_2 ) of the electrostatic potentials on each sphere is :

An electric field 'E' whose direction is radially outward varies as distance from origin 'r' as shown in the graph E is taken as positive if its direction is away from the origin. Then the work done by electric field on a 2 C charge if it is taken from (1,1,0) to (3,0,0) is :