A solid sphere of radius R and mass density `rho` is surrounded by another outer sphere of density `2 rho`. Let `E_(P)` is gravitational field at P and `E_(Q)` is at Q. If the ratio of `E_(Q)//E_(P)=3k//4`. Find the value of k.

A solid sphere of radius R has a mass distributed in its volume of mass density rho=rho_(0) r, where rho_(0) is constant and r is distance from centre. Then moment of inertia about its diameter is

A solid sphere having radius R and uniform charge density rho has a cavity of radius R/2 as shown in figure then the value of |(E_(A)/(E_(B)))| = (m)/(17) .Find the value of m

A solid sphere having radius R and uniform charge density rho has a cavity of radius R/2 as shown in figure.Find the value of |E_A /E_B|

A solid sphere of radius R has a charge Q distributed in its volume with a charge density rho=kr^a , where k and a are constants and r is the distance from its centre. If the electric field at r=(R)/(2) is 1/8 times that r=R , find the value of a.

For an infinitely long solid cylinder of radius R having a uniform density , the gravitational field at a distance r_(1) is E_(1) and at a distance r_(2) is E_(2) , then

Mass density of sphere having radius R varies as rho = rho_0(1-r^2/R^2) . Find maxium magnitude of gravitational field

A cavity of radius r is present inside a solid dielectric sphere of radius R, having a volume charge density of rho . The distance between the centres of the sphere and the cavity is a. An electron e is kept inside the cavity at an angle theta=45^(@) as shown. the electron (mass m and -e) touches the sphere again after time ((P sqrt(2) mr epsi_(0))/(e a rho))^(1//2) ? Find the value of P. Neglect gravity.

A sphere of radius R contains charge density rho(r )=A (R-r ) , for 0 lt r lt R . The total electric charge inside the sphere is Q. The value of A in terms of Q and R is