試題詳解

24. Two point charges q₁=2.1×10^-8C and q₂ = −4q₁ are fixed in two places 50 cm apart. The point charge  q₁ is at the right side of  q₂ . Find the point at which the electric field is zero, along the straight line passing through the two charges. The point is .
(A) 50 cm to the right of  q₁ 
(B) 50 cm to the left of  q₂ 
(C) 100 cm to the right of  q₁ 
(D) 100 cm to the left of q₂ 
(E) The middle point between  q₁ and  q₂