FBISE, NCP & NBF-aligned resources for Classes 9–12
Browse by Class
Browse by Type
Physics Chapter 10 : Topic 5
Charged Spherical Conductors
1 / 30
For a point outside a charged spherical conductor, the electric field is equivalent to that produced by:
Reasoning: Due to spherical symmetry, the external electric field of a charged sphere is the same as if all charge were concentrated at its center.
2 / 30
The charge on a spherical conductor can be considered as a point charge at its center when observing:
Reasoning: The point charge approximation applies only to points outside the spherical conductor.
3 / 30
A charged spherical conductor of charge $\mathbf{(Q)}$ produces an electric field outside it. The field strength at distance $\mathbf{(r)}$ from its center is:
Reasoning: Outside the sphere, the field behaves exactly like a point charge located at the center.
4 / 30
The reason a spherical conductor behaves like a point charge externally is:
Reasoning: Symmetrical charge distribution makes the external field identical to that of a point charge at the center.
5 / 30
A charged conducting sphere has radius $\mathbf{0.1\ m}$. A point $\mathbf{0.5\ m}$ away from its center experiences an electric field. The distance used in Coulomb’s law is:
Reasoning: For external points, distance is measured from the center of the sphere.
6 / 30
The electric field outside a charged spherical conductor decreases with distance because:
Reasoning: Outside the sphere: $\mathbf{E =}$ $\frac{\mathbf{kQ}}{\mathbf{r}^{\mathbf{2}}}$ $\mathbf{\Longrightarrow}$ So, field decreases as $\mathbf{r}^{\mathbf{2}}$ increases.
7 / 30
A charged spherical conductor behaves electrically like a point charge located at:
Reasoning: The equivalent point charge is placed at the center due to spherical symmetry.
8 / 30
If the charge on a spherical conductor is doubled, the electric field at an external point becomes:
Reasoning: $\mathbf{E =}$ $\frac{\mathbf{kQ}}{\mathbf{r}^{\mathbf{2}}}$ $\mathbf{\Longrightarrow}$ Field is directly proportional to charge.
9 / 30
If the distance from the center of a charged sphere is doubled, the external electric field becomes:
Reasoning: $\mathbf{E \propto}$ $\frac{\mathbf{1}}{\mathbf{r}^{\mathbf{2}}}$ $\mathbf{\Longrightarrow}$ Doubling distance reduces field to one-fourth.
10 / 30
The electric field outside a spherical conductor depends on:
Reasoning: External field depends on $\mathbf{(Q)}$ and $\mathbf{(r)}$ according to Coulomb’s law.
11 / 30
A charged spherical conductor has the same external electric field as:
Reasoning: The entire charge of the sphere can be considered concentrated at its center for external points.
12 / 30
For a charged spherical conductor, the electric field at an external point is calculated using:
Reasoning: The equivalent point charge is located at the center.
13 / 30
A charged metal sphere and a point charge have the same total charge. At the same external distance from their centers, their electric fields are:
Reasoning: Outside a spherical conductor, the field is identical to that of a point charge.
14 / 30
The electric field inside a conductor in electrostatic equilibrium is:
Reasoning: Charges rearrange themselves until the internal electric field becomes zero.
15 / 30
The charge on a conductor resides on its:
Reasoning: Excess charge on a conductor exists on its outer surface in electrostatic equilibrium.
16 / 30
A spherical conductor carries charge $\mathbf{(Q)}$. At an external point, replacing the sphere by a point charge at the center:
Reasoning: The approximation gives exactly the same external field due to spherical symmetry.
17 / 30
A point outside a charged sphere is located at distance $\mathbf{(3R)}$ from its center. The electric field depends on:
Reasoning: External field calculations use the distance from the center.
18 / 30
Why cannot a charged spherical conductor always be treated as a point charge?
Reasoning: The point charge model applies only for external points.
19 / 30
A conducting sphere and a point charge have equal charge. At a point far away from both, their fields are:
Reasoning: At external points, the sphere behaves like a point charge, especially at large distances.
20 / 30
The external electric field of a charged spherical conductor proves that:
Reasoning: Symmetry allows the field to be represented by a central point charge.
21 / 30
A spherical conductor has charge $\mathbf{5\mu C}$. The electric field outside it is calculated using:
Reasoning: The total charge is considered concentrated at the center for external points.
22 / 30
The electric field lines outside a charged sphere are:
Reasoning: The external field has radial symmetry.
23 / 30
For a negatively charged spherical conductor, external field lines:
Reasoning: Negative charges attract positive test charges, so field lines point inward.
24 / 30
The radius of a spherical conductor affects the external field:
Reasoning: Outside the sphere, the field depends on distance from the center.
25 / 30
A charged spherical conductor produces an external field because:
Reasoning: Excess charge on the conductor produces an external electric field.
26 / 30
A charged sphere has radius $\mathbf{(R)}$. A point at distance $\mathbf{(r)}$ from the center where $\mathbf{(r}\mathbf{>}\mathbf{R}\mathbf{)}$ experiences:
Reasoning: For $\mathbf{(r}\mathbf{>}\mathbf{R}\mathbf{)}$, the sphere behaves as a point charge.
27 / 30
The concept of replacing a charged sphere by a point charge is based on:
Reasoning: Spherical symmetry makes the external field identical to that of a central point charge.
28 / 30
If a charged sphere is observed from an external point, the observer cannot distinguish it electrically from:
Reasoning: Both produce the same external electric field.
29 / 30
The mathematical similarity between a charged sphere and a point charge outside the sphere is:
Reasoning: External field follows: $\mathbf{E =}$ $\frac{\mathbf{kQ}}{\mathbf{r}^{\mathbf{2}}}$
30 / 30
The statement “charge on a spherical conductor may be considered as a point charge at its center” is valid:
Reasoning: The approximation is valid only outside a spherical conductor.
Your score is
Restart quiz
