Advertisements
Advertisements
प्रश्न
Careful measurement of the electric field at the surface of a black box indicates that the net outward flux through the surface of the box is 8.0 × 103 N m2/C.
- What is the net charge inside the box?
- If the net outward flux through the surface of the box were zero, could you conclude that there were no charges inside the box? Why or Why not?
Advertisements
उत्तर
(a) Φ = 8 × 103 N m2 C−1
`q/ε_0 = 8 xx 10^3` N m2 C−1
∴ q = 8 × 103 ε0
= 8 × 103 × 8.85 × 10−12
= 7.08 × 10−8 C
(b) As Φ = 0
`q_"net"/ε_0 = 0`
∴ `q_"net" = 0`
Even though a closed surface may have internal charges, the net charge it contains is zero.
संबंधित प्रश्न
Write S.I unit of electric flux.
Consider two hollow concentric spheres, S1 and S2, enclosing charges 2Q and 4Q respectively as shown in the figure. (i) Find out the ratio of the electric flux through them. (ii) How will the electric flux through the sphere S1 change if a medium of dielectric constant 'εr' is introduced in the space inside S1 in place of air ? Deduce the necessary expression
What is the net flux of the uniform electric field of previous question through a cube of side 20 cm oriented so that its faces are parallel to the coordinate planes?
A uniformly charged conducting sphere of 2.4 m diameter has a surface charge density of 80.0 μC/m2.
- Find the charge on the sphere.
- What is the total electric flux leaving the surface of the sphere?
Two charges of magnitudes −2Q and +Q are located at points (a, 0) and (4a, 0) respectively. What is the electric flux due to these charges through a sphere of radius ‘3a’ with its centre at the origin?
If the flux of the electric field through a closed surface is zero,
(a) the electric field must be zero everywhere on the surface
(b) the electric field may be zero everywhere on the surface
(c) the charge inside the surface must be zero
(d) the charge in the vicinity of the surface must be zero
Electric charges are distributed in a small volume. The flux of the electric field through a spherical surface of radius 10 cm surrounding the total charge is 25 V m. The flux over a concentric sphere of radius 20 cm will be _____________ .
If the flux associated with a coil changes at the rate of 360 webers every 4 minutes, then the induced e.m.f. is ______
Total electric flux coming out of a unit positive charge kept in air is ______.
The electric field intensity due to an infinite cylinder of radius R and having charge q per unit length at a distance rir r(r > R) from its axis is ______.
The S.I. unit of electric flux is ______
What will be the total flux through the faces of the cube (figure) with side of length a if a charge q is placed at
- A: a corner of the cube.
- B: mid-point of an edge of the cube.
- C: centre of a face of the cube.
- D: mid-point of B and C.
The electric charges are distributed in a small volume. The flux of the electric field through a spherical surface of radius 10 cm surrounding the total charge is 20 V-m. The flux over a concentric sphere of radius 20 cm will be ______.
A hollow sphere of radius R has a point charge q at its centre. Electric flux emanating from the sphere is X. How will the electric flux change, if at all, when charge q is replaced by an electric dipole?
A hollow cylinder has a charge of 'q' C within it. If 𝜙 is the electric flux associated with the curved surface B, the flux linked with the plane surface A will be ______.
An electric field is given by `(6 hat i + 5 hat j + 3 hat k)` N/C. The electric flux through a surface area `30 hat i` m2 lying in YZ-plane (in SI unit) is ______.
