Home › Maharashtra HSC Class 12 (Science) › physics › Electrostatics › A 10 cm sphere carries charge 1 μC. The field ma…
A 10 cm sphere carries charge 1 μC. The field magnitude at 30 cm from its centre is
A9×10⁵ N/C
B10⁴ N/C
C3×10⁵ N/C
D10⁵ N/C
Answer & Solution
Correct answer: D. 10⁵ N/C
1. At r = 0.3 m we are outside the sphere so E = q/(4πε₀r²).
2. Substitute q = 10⁻⁶ C, 1/(4πε₀) = 9×10⁹: E = (9×10⁹ × 10⁻⁶)/(0.3)².
3. E = 9×10³/0.09 = 10⁵ N/C.
_Source: Maharashtra Balbharati Std XII Physics, Ch 8 "Electrostatics" §8.2.1 Example 8.1_
Related questions
If a positive point charge is placed at the centre of a spherical conducting shell of radiThe SI unit of electric field isFor a charge distribution with volume density ρ, the total charge Q equalsThe electric flux through a closed surface enclosing a charge of +5 μC is (ε₀ = 8.85 × 10⁻Two charges +q and −q of equal magnitude are placed at the corners A and B of an equilaterThe principle of quantisation of electric charge is stated asAn electric dipole in a uniform electric field E experiencesThe electric field on the axial line of a short electric dipole at distance r is