Question

Point R is 0.4 m from a 2C charge. Find the electric field at point R.

1.1x1011 N/C
3.4x1011 N/C
5.4x1011 N/C
2.7x1011 N/C

Answer 1

We know, E = 1/4π∈ * q/r²
Here, 1/4π∈ = 9 × 10⁹
q = 2 C
r = 0.4

Substitute their values,
E = 9 × 10⁹ * 2/(0.4)²
E = 9 × 10⁹ * 2/0.16
E = 9 × 10⁹ * 12.5
E = 112.5 × 10⁹ N/C

So, Your Final Answer would be 1.125 × 10¹¹ N/C

Hope this helps!