Home
Class 12
PHYSICS
A positively charge sphere of radius r0 ...

A positively charge sphere of radius `r_0` carries a volume charge density `rho`. A spherical cavity of radius `r_0//2` is then scooped out and left empty. `C_1` is the center of the sphere and `C_2` that of the cavity. What is the direction and magnitude of the electric field at point B?

A

`(17rhor_0)/(54epsilon_0)`left

B

`(rhor_0)/(6epsilon_0)` left

C

`(17rhor_0)/(54epsilon_0)`right

D

`(rhor_0)/(6epsilon_0)`right

Text Solution

Verified by Experts

The correct Answer is:
A

a. Electric field on surface of a uniformly charged sphere is given
by
`Q/(4piepsilon_0R^2) = (rhoR)/(3epsilon_0)`
Electric field at outside point is given by
`E = Q/(4piepsilon_0r^2) = (rhoR^3)/(3epsilon_0r^2)`
`E_B = E_(whol e sphere) - E_(cavity)`
`= (rhor_0)/(3epsilon_0) - (rho(r_0/2)^3)/(3epsilon_0(3r_0/2)^2) = (17rhor_0)/(54epsilon_0)`.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ELECTRIC FLUX AND GAUSS LAW

    CENGAGE PHYSICS|Exercise Multiple Correct|8 Videos
  • ELECTRIC FLUX AND GAUSS LAW

    CENGAGE PHYSICS|Exercise Comprehension|36 Videos
  • ELECTRIC FLUX AND GAUSS LAW

    CENGAGE PHYSICS|Exercise Subjective|12 Videos
  • ELECTRIC CURRENT AND CIRCUIT

    CENGAGE PHYSICS|Exercise Interger|8 Videos
  • ELECTRIC POTENTIAL

    CENGAGE PHYSICS|Exercise DPP 3.5|14 Videos

Similar Questions

Explore conceptually related problems

A spherical cavity of radius r is made in a conducting sphere of radius 2 r.A charge q is kept at the centre of cavity as shown in the figure.Find the magnitude of the total electric field at (4r 0) .

A spherical cavity of radius r is made in a conducting sphere of radius 2r. A charge 9 is kept at the centre of cavity as shown in the figure. Find the magnitude of the total electric field at(4r 0). у r (0 0) х 9 2r

Knowledge Check

  • A positively charged sphere of radius r_(0) carries a volume charge density rho_(E) (Figure). A spherical cavity of radius r_(0)//2 is then scooped out and left empty, as shown. What is the direction and magnitude of the electric field at point B?

    A
    `(17rhor_(0))/(54in_(0)) l eft`
    B
    `(rho_(0))/(6in_(0))l eft`
    C
    `(17rhor_(0))/(54in_(0))right`
    D
    `(rhor_(0))/(6in_(0)) right`
  • A solid non-conducting sphere of radius R is charged with a uniform volume charge density rho . Inside the sphere a cavity of radius r is made as shown in the figure. The distance between the centres of the sphere and the cavity is a. An electron of charge 'e' and mass 'm' is kept at point P inside the cavity at angle theta = 45^(@) as shown. If at t = 0 this electron is released from point P, calculate the time it will take to touch the sphere on inner wall of cavity again.

    A
    `sqrt((3Rm epsilon_(0)r)/(e rho a))`
    B
    `sqrt((6m epsilon_(0)r)/(e rho a))`
    C
    `sqrt((6sqrt(3) m epsilon_(0)R)/(e rho a))`
    D
    `sqrt((6sqrt(2)m epsilon_(0)r)/(e rho a))`
  • The figure represents a solid uniform sphere of mass M and radius R . A spherical cavity of radius r is at a distance a from the centre of the sphere. The gravitational field inside the cavity is

    A
    non - uniform
    B
    towards the center of the cavity
    C
    directly proportional to `a`
    D
    All of these
  • Similar Questions

    Explore conceptually related problems

    A uniformly charged hemisphere of radius b and charge density rho has a hemispherical cavity of radius a(a=b/2) cut from its centre. If the potential at the centre of the cavity is (nrhob^(2))/(16epsilon_(0)) then n=?

    A sphere of radius R has a uniform volume density rho . A spherical cavity of radius b, whose center lies at veca , is removed from the sphere. i. Find the electric field at any point inside the spherical cavity. ii. Find the electric field outside the cavity (a) at points inside the large sphere but outside the cavity and (b) at points outside the large sphere.

    A system consists of a uniformly charged sphere of radius R and a surrounding by a medium with volume charge density rho =a/r , where alpha is a positive constant and r is the distance from the centre of the sphere. If NalphaR^(2) is the charge on the sphere when the electric field intensity outside the sphere is independent of r. What is the value of N ?

    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 sphere of radius R carries charge such that its volume charge density is proportional to the square of the distance from the centre. What is the ratio of the magnitude of the electric field at a distance 2 R from the centre to the magnitude of the electric field at a distance of R//2 from the centre?