Electric field and field lines - One Line Questions
1.
The electric field strength at a distance r from a point charge Q is proportional to: —
1/r²
2.
Electric field lines are parallel and equally spaced in the field of: —
A uniformly charged infinite plane
3.
Electric field lines are perpendicular to the surface of a conductor in electrostatic equilibrium. —
Always true
4.
Electric field lines can never cross each other because: —
The electric field at a point must have a unique direction
5.
The electric field lines for a system of two identical negative charges: —
Repel each other
6.
In a region of uniform electric field, electric field lines are: —
Parallel and equally spaced
7.
The electric field lines due to a system of two identical positive charges are: —
Repelling each other
8.
Consider a large sheet of charge with uniform surface charge density σ. The electric field lines near the sheet are: —
9.
Which property of electric field lines indicates the direction of the electric field at a point? —
Direction of the tangent to the line
10.
If the electric field is E, and a small area element is dA, the electric flux through this element is given by: —
E . dA
11.
The electric field lines are always directed from regions of higher electric potential to regions of lower electric potential. This means: —
Electric field is perpendicular to equipotential lines.
12.
Electric field lines are drawn to be perpendicular to the equipotential surfaces. This implies: —
Work done in moving a charge along an equipotential surface is zero.
13.
Electric field lines are used to visualize: —
Electric field
14.
What is the electric field at an infinite distance from a point charge? —
Zero
15.
The electric field is conservative. This means that the work done by the electric field in moving a charge between two points is: —
Zero
16.
Consider a point charge q. The electric field lines are denser closer to the charge. This illustrates that the electric field strength: —
Decreases with distance from the charge
17.
What is the electric field at the center of an electric dipole? —
Zero
18.
What is the electric field at the center of a uniformly charged ring? —
Zero
19.
What is the electric field inside a hollow charged conductor? —
Zero
20.
If the number of electric field lines passing through a surface is N, and the surface area is A, what is the approximate electric field strength if the lines are perpendicular to the surface? —
N / A
21.
Electric field lines originate from which type of charge? —
Positive charge
22.
If the electric field lines are diverging from a point, it indicates the presence of a: —
Positive charge
23.
What is the unit of electric field strength? —
Newton per Coulomb (N/C)
24.
What is the unit of electric flux? —
Volt-meter (V·m)
25.
The electric field strength is proportional to the: —
Density of field lines
26.
Electric field lines terminate on which type of charge? —
Negative charge
27.
What is the electric field at a distance r from an infinitely long uniformly charged wire with linear charge density λ? —
Proportional to 1/r
28.
What is the net electric flux through a closed surface enclosing a net charge Q? —
Q / ε₀
29.
Which of the following represents the electric field of a dipole? —
A pattern of curved lines originating from the positive charge and terminating on the negative charge
30.
For a positive point charge, electric field lines are directed: —
Radially outwards
31.
For a negative point charge, electric field lines are directed: —
Radially inwards
32.
The electric field lines due to a system of two equal and opposite charges (a dipole) are: —
Elliptical or curved lines starting from positive and ending on negative
33.
In the case of an electric dipole, the electric field lines are: —
Curved lines starting from the positive charge and ending on the negative charge
34.
For a uniformly charged sphere, the electric field outside the sphere behaves as if the charge were concentrated at: —
The center of the sphere
35.
Electric field lines map out the direction and magnitude of the electric field. Which statement is true? —
The number of lines originating from a positive charge is proportional to the magnitude of the charge.
36.
What does the density of electric field lines represent? —
The magnitude of the electric field
37.
Electric field lines are perpendicular to the surface of a conductor because: —
There is no electric field parallel to the surface of a conductor in equilibrium
38.
Electric field lines are drawn such that the number of lines per unit area perpendicular to the lines is proportional to: —
The electric field strength
39.
The electric field strength is given by E = F/q. Here, q is: —
A positive test charge
40.
Which of the following statements about electric field lines is incorrect? —
They can form closed loops.
41.
What happens to the electric field lines when they enter a conducting medium? —
They terminate on the surface of the conductor
42.
Which of the following statements about electric field lines is true? —
They indicate the direction of the force on a positive test charge.
43.
Which of the following correctly describes the electric field lines from a system of one positive and one negative charge of equal magnitude? —
They start from the positive charge and end on the negative charge, forming curved paths.
44.
The electric field lines are closer together where the electric field is: —
Strong
45.
Can electric field lines intersect each other? —
No, electric field lines never intersect
46.
If two charges +q and -q are placed at a distance d apart, the electric field at the midpoint of the line joining them is: —
Maximum
47.
What is the electric field at the surface of a charged conductor? —
σ/ε₀, where σ is the surface charge density
48.
What is the electric field at the surface of a charged conductor in vacuum? —
σ / ε₀
49.
What is the electric field at the center of a uniformly charged solid sphere? —
Zero
50.
What is the electric field at the surface of a charged conductor if it is placed in a dielectric medium of relative permittivity εr? —
σ / (ε₀εr)