Advertisements
Advertisements
प्रश्न
Consider a uniform electric field E = 3 × 103 `hat i` N/C.
- What is the flux of this field through a square of 10 cm on a side whose plane is parallel to the yz plane?
- What is the flux through the same square if the normal to its plane makes a 60° angle with the x-axis?
Advertisements
उत्तर
(a) Area of square, A = a2 = 102 = 100 cm2
= 100 × 10-4 m2
= 10−2 m2
Since the plane lies on the y-z-axis, the area vector `vecA` points in the same direction.
i.e., `vecA = (10^-2 hati) m^2`
∴ Electric Flux through the square is:
Φ = `vecE · vecA` = `(3 xx 10^3 hati)*(10^-2 hati)`
= 3 × 101
or Φ = 30 V-m
(b) When normal to plane, i.e., `vecA` makes an angle of 60° with `vecE`, then
Φ' = EA cos 60°
= `3 xx 10^3 xx 10^-2 xx 1/2`
= 1.5 × 101
or Φ' = 15 V-m
संबंधित प्रश्न
Define electric flux.
Given a uniform electric field `vecE=5xx10^3hati`N/C, find the flux of this field through a square of 10 cm on a side whose plane is parallel to the y-z plane. What would be the flux through the same square if the plane makes a 30° angle with the x-axis ?
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
Define Electric Flux.
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?
A circular ring of radius r made of a non-conducting material is placed with its axis parallel to a uniform electric field. The ring is rotated about a diameter through 180°. Does the flux of the electric field change? If yes, does it decrease or increase?
It is said that any charge given to a conductor comes to its surface. Should all the protons come to the surface? Should all the electrons come to the surface? Should all the free electrons come to the surface?
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
A uniform electric field of intensity 400 N/C, exists in a certain region. How much flux will cross a given area of 10 cm2 in this region, if the area vector is inclined at 60° to the direction of the field?
A charge 'Q' µC is placed at the centre of a cube. The flux through one face and two opposite faces of the cube is respectively ______.
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 ______.
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 it is `phi`. If both the charge and the radius of the sphere are doubled, electric flux emanating from the sphere will ______.
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 radius of the sphere is doubled?
