A point charge of 10⁻⁸ C is placed at origin. The work done in moving a point charge 2 C from point A(4,4,2) m to B(2,2,1) m is _ _ _ _ J. ( 1 4 _ o =9 10⁹ . in SI units )

Step-by-step solution

Distance from origin to A: r_A = 4^2 + 4^2 + 2^2 = 6 m Distance from origin to B: r_B = 2^2 + 2^2 + 1^2 = 3 m Work done: W = q₂(V_B - V_A) = q₂ q₁ 4 ₀ ( 1 r_B - 1 r_A ) = 2 10⁻⁶ 9 10^9 10⁻⁸ ( 1 3 - 1 6 ) = 18 10⁻⁵ 1 6 = 30 10⁻⁶ J