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Conductors, Electrostatic Shielding and Dielectrics

Latest questions in this category.

30 questions

Three charges \( +11 \, \mu\text{C} \), \( -8 \, \mu\text{C} \), and \( +6 \, \mu\text{C} \) are at \( (0, 0, 0) \), \(

**Electrostatic shielding** inside hollow conducting shell field zero when no charges inside, regardless of external field, because free charges redistribute on outer surface to cancel external field inside conductor, E=0 inside material in equilibrium, consequence of Gauss's law and conductor property. Distances: r₁ = √(11² + 11²) = 11√(2) m , r₂ = 11 m , r₃ = 11 m . V = 9 × 10⁹ ( (11 × 10⁻⁶/11√(2)) + (-8 × 10⁻⁶/11) + (6 × 10⁻⁶/11) ) . V = 9 × 10⁹ ( (11 × 10⁻⁶/15.556) - (8 × 10⁻⁶/11) + (6 × 10⁻⁶/11) ) . V = 9 × 10⁹ (

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A point charge \( Q = 9 \times 10^{-9} \, \text{C} \) is placed at the origin. Calculate the potential at a point 3 m aw

**Dielectric polarization** when slab inserted, bound charges appear reducing effective field, capacitance increases by factor K, potential difference for constant charge V = Q/C decreases, for constant voltage charge increases. Dielectric constant K = ε/ε₀ >1, e.g., K≈5 for glass. Potential due to a point charge: V = (1/4 π ε₀) (Q/r) . Substitute: V = 9 × 10⁹ × (9 × 10⁻⁹/3) = 9 × 10⁹ × 3 × 10⁻⁹ = 27 V . Using V = kQ/r, U = k q₁q₂/r, E = -dV/dr, C = ε₀A/d, 1/C_eq series, C_eq = ΣC parallel, U = ½ C V² and common potential V =

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A point charge \( Q = 18 \times 10^{-9} \, \text{C} \) is placed at the origin. Calculate the potential at a point 6 m a

**Electrostatic shielding** inside hollow conducting shell field zero when no charges inside, regardless of external field, because free charges redistribute on outer surface to cancel external field inside conductor, E=0 inside material in equilibrium, consequence of Gauss's law and conductor property. Potential due to a point charge: V = (1/4 π ε₀) (Q/r) . Substitute: V = 9 × 10⁹ × (18 × 10⁻⁹/6) = 9 × 10⁹ × 3 × 10⁻⁹ = 27 V . Using V = kQ/r, U = k q₁q₂/r, E = -dV/dr, C = ε₀A/d, 1/C_eq series, C_eq = ΣC parallel, U = ½ C V² and common potential V

Ref: NCERT > Physics Book > Electrostatic Potential and Capacitance > Conductors, Electrostatic Shielding and Dielectrics

Why does the electric field inside a charged spherical shell vary linearly with distance from the center when a uniform

**Dielectric polarization** when slab inserted, bound charges appear reducing effective field, capacitance increases by factor K, potential difference for constant charge V = Q/C decreases, for constant voltage charge increases. Dielectric constant K = ε/ε₀ >1, e.g., K≈5 for glass. Electrostatic Potential and Capacitance typically assumes no charge inside a spherical shell, leading to E = 0 . However, if misinterpreted as a charged dielectric sphere (common in advanced contexts but not in the PDF), the field varies as E ∝ r . Since the PDF context implies an empty shell or uniform shell charge, E = 0 . Assuming a misinterpretation, the correct context

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Why does the potential energy of a system of two charges depend only on their separation and not on their orientation in

**Electrostatic shielding** inside hollow conducting shell field zero when no charges inside, regardless of external field, because free charges redistribute on outer surface to cancel external field inside conductor, E=0 inside material in equilibrium, consequence of Gauss's law and conductor property. The potential energy between two point charges is U = (1/4 π ε₀) (q₁ q₂/r) , where r is the distance between them. This expression depends only on the magnitude of the separation r , not on the direction or orientation of the line joining the charges in space, because the Coulomb force is isotropic (depends only on distance) and the potential is a

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Two charges \( 6 \, \mu\text{C} \) and \( -3 \, \mu\text{C} \) are at \( (10, 0, 0) \) and \( (-10, 0, 0) \, \text{cm} \

**Conductor in electrostatic equilibrium** has E=0 inside, charges reside on surface, potential constant throughout conductor. Hollow shell with no internal charge has zero field inside cavity, even if external field present, charges on outer surface screen interior, principle used in Faraday cage. Distance to midpoint = 0.1 m. V = 9 × 10⁹ ( (6 × 10⁻⁶/0.1) + (-3 × 10⁻⁶/0.1) ) = 9 × 10⁹ × (3 × 10⁻⁶/0.1) = 2.7 × 10⁵ V . Using V = kQ/r, U = k q₁q₂/r, E = -dV/dr, C = ε₀A/d, 1/C_eq series, C_eq = ΣC parallel, U = ½ C V² and common potential V

Ref: NCERT > Physics Book > Electrostatic Potential and Capacitance > Conductors, Electrostatic Shielding and Dielectrics

Three charges \( +10 \, \mu\text{C} \), \( -7 \, \mu\text{C} \), and \( +5 \, \mu\text{C} \) are at \( (0, 0, 0) \), \(

**Electrostatic shielding** inside hollow conducting shell field zero when no charges inside, regardless of external field, because free charges redistribute on outer surface to cancel external field inside conductor, E=0 inside material in equilibrium, consequence of Gauss's law and conductor property. Distances: r₁ = √(10² + 10²) = 10√(2) m , r₂ = 10 m , r₃ = 10 m . V = 9 × 10⁹ ( (10 × 10⁻⁶/10√(2)) + (-7 × 10⁻⁶/10) + (5 × 10⁻⁶/10) ) . V = 9 × 10⁹ ( (10 × 10⁻⁶/14.142) - (7 × 10⁻⁶/10) + (5 × 10⁻⁶/10) ) . V = 9 × 10⁹ (

Ref: NCERT > Physics Book > Electrostatic Potential and Capacitance > Conductors, Electrostatic Shielding and Dielectrics

A spherical conductor of radius 4 cm has a charge of \( 8 \times 10^{-8} \, \text{C} \). What is the potential at its su

**Electrostatic shielding** inside hollow conducting shell field zero when no charges inside, regardless of external field, because free charges redistribute on outer surface to cancel external field inside conductor, E=0 inside material in equilibrium, consequence of Gauss's law and conductor property. Potential at the surface: V = (1/4 π ε₀) (Q/R) . V = 9 × 10⁹ × (8 × 10⁻⁸/0.04) = 9 × 10⁹ × 2 × 10⁻⁶ = 18000 V . Using V = kQ/r, U = k q₁q₂/r, E = -dV/dr, C = ε₀A/d, 1/C_eq series, C_eq = ΣC parallel, U = ½ C V² and common potential V = Q_total/C_total, result

Ref: NCERT > Physics Book > Electrostatic Potential and Capacitance > Conductors, Electrostatic Shielding and Dielectrics

An electric dipole with moment \( p = 7 \times 10^{-9} \, \text{C m} \) lies along the x-axis. What is the potential at

**Electrostatic shielding** inside hollow conducting shell field zero when no charges inside, regardless of external field, because free charges redistribute on outer surface to cancel external field inside conductor, E=0 inside material in equilibrium, consequence of Gauss's law and conductor property. Along the dipole axis ( θ = 0° ): V = (1/4 π ε₀) (p/r²) . V = 9 × 10⁹ × (7 × 10⁻⁹/4²) = 9 × 10⁹ × (7 × 10⁻⁹/16) = 3.9375 V . Using V = kQ/r, U = k q₁q₂/r, E = -dV/dr, C = ε₀A/d, 1/C_eq series, C_eq = ΣC parallel, U = ½ C V² and common

Ref: NCERT > Physics Book > Electrostatic Potential and Capacitance > Conductors, Electrostatic Shielding and Dielectrics

A spherical conductor of radius 3 cm has a charge of \( 3 \times 10^{-8} \, \text{C} \). What is the potential at its su

**Dielectric polarization** when slab inserted, bound charges appear reducing effective field, capacitance increases by factor K, potential difference for constant charge V = Q/C decreases, for constant voltage charge increases. Dielectric constant K = ε/ε₀ >1, e.g., K≈5 for glass. Potential at the surface: V = (1/4 π ε₀) (Q/R) . V = 9 × 10⁹ × (3 × 10⁻⁸/0.03) = 9 × 10⁹ × 10⁻⁶ = 9000 V . Using V = kQ/r, U = k q₁q₂/r, E = -dV/dr, C = ε₀A/d, 1/C_eq series, C_eq = ΣC parallel, U = ½ C V² and common potential V = Q_total/C_total, result 9000 V follows, reflecting potential-capacitance relations.

Ref: NCERT > Physics Book > Electrostatic Potential and Capacitance > Conductors, Electrostatic Shielding and Dielectrics

A charged particle is placed in a region where the electric potential varies linearly with distance. What can be said ab

**Conductor in electrostatic equilibrium** has E=0 inside, charges reside on surface, potential constant throughout conductor. Hollow shell with no internal charge has zero field inside cavity, even if external field present, charges on outer surface screen interior, principle used in Faraday cage. The electric field E is related to potential V by E = -(dV/dx) . If V varies linearly with distance ( V = kx + c ), then (dV/dx) = k , a constant. Thus, E = -k , meaning the electric field is uniform (constant magnitude and direction) in the direction opposite to the gradient of V , consistent with a linear

Ref: NCERT > Physics Book > Electrostatic Potential and Capacitance > Conductors, Electrostatic Shielding and Dielectrics

An electric dipole with moment \( p = 3 \times 10^{-9} \, \text{C m} \) lies along the x-axis. What is the potential at

**Electrostatic shielding** inside hollow conducting shell field zero when no charges inside, regardless of external field, because free charges redistribute on outer surface to cancel external field inside conductor, E=0 inside material in equilibrium, consequence of Gauss's law and conductor property. In the equatorial plane ( θ = 90° ): V = (1/4 π ε₀) (p cos θ/r²) . Since cos 90° = 0 , V = 0 V . Using V = kQ/r, U = k q₁q₂/r, E = -dV/dr, C = ε₀A/d, 1/C_eq series, C_eq = ΣC parallel, U = ½ C V² and common potential V = Q_total/C_total, result 0 V follows, reflecting potential-capacitance relations.

Ref: NCERT > Physics Book > Electrostatic Potential and Capacitance > Conductors, Electrostatic Shielding and Dielectrics