Answer:
0.7071D
Explanation:
Electric field strength is given as:
E = kq/rĀ²
Where k = Coulumbs constant
q = charge
r = distance
When r = D, E = 1000 N/C
=> 1000 = kq/DĀ²
=> kq = 1000DĀ² ______ (1)
When E = 2000 N/C,
2000 = kq/rĀ²
kq = 2000rĀ² ____________ (2)
Since k is a constant and q is the same, equate (1) & (2):
2000rĀ² = 1000DĀ²
=> rĀ² = 1000/2000 DĀ²
rĀ² = 0.5DĀ²
=> r = 0.7071D