Question

v (x )=ax- bx^ 3 where a and b are constants .At which point on the x axis ,the field intensity becomes 0​

Answer 1

Answer: x = √(a/3b)

Explanation: E = - dV/dx

⇒ E = - d(ax- bx^3)/dx

⇒ E = - ( a - 3bx^2) = 3bx^2 - a

⇒ E = 0 = 3bx^2 - a

⇒    3bx^2 = a

⇒      x^2 = a/2b

⇒     x = √(a/2b)