Chapter 1 Electric Charges and Fields
Top questions
See all →- What is the force between two small charged spheres having charges of 2 x 10-7C and 3 x 10-7C placed 30 cm apart q₁ = 2 x 10^(-7 )C, q₂ = 3 x 10^(-7 )C, r = 30 cm = 30 x 10^(-2 )m F = 9 x 10⁹ = 9 x 10⁹ x frac2 × 10⁻⁷ × 3 × 10⁻⁷(30 × 10⁻²)² = 0.06 x 10^(... 1
- The electrostatic force on a small sphere of charge 0.4 pC due to another small sphere of charge – 0.8 μC in air is 0.2 q₁ = 0.4 μC = 0.4 x 10^(-6 )C, q₂ = – 0.8μC = – 0 .8 x 10^(-6 )C, F = 0.2 N (a) F = 9 x 10⁹ r² = 9 x 10⁹ x fracq₁ q₂~F = frac9 × 10⁹ × 0.4 ×... 1
- An electric dipole with dipole moment 4 x 10-9 Cm is aligned at 30° with the direction of a uniform electric field p = 4 x 10^(-9 )Cm, θ = 30°, E = 5 x 10^(4 )NC⁻¹ τ = pE sin θ = 4 x 10⁻⁹ x 5 x 10⁴ x sin 30° = 4 x 10⁻⁹ x 5 x 10⁴ x 1 / 2 = 10 x 10^(-5 )Nm... 1
- A polythene piece rubbed with wool is found to have a negative charge of 3 x 10-7C. (a) Estimate the number q = 3 x 10^(-7 )C (a) q = ne, n = q / e = frac3 × 10⁻⁷1.6 × 10⁻¹⁹ ≈ 2 x 10¹² (Since polythene has negative charge, electrons are transferred... 1
- Consider a uniform electric field E = 3 x 103\(\hat { i } \) N/C. (a) What is the flux of this field through (a) E = 3 x 10^(3 )NC⁻¹, r = 10 x 10⁻²m Φ = E x Area = 3 x 10³ x (10 x 10⁻²)² = 30 Nm²C⁻¹ (b) Φ = E x Area x cos 60° = 30 x 1 / 2 = 15 Nm²C-... 1
- What is the net flux of the uniform electric field of Exercise.15 through a cube of side 20 cm oriented so that its Zero. The number of lines entering the cube is the same as the number of lines leaving the cube. 1