A very long straight wire has charge per unit length 1.44×10-10C/m.

question:

At what distance from the wire is the magnitude of the electric field equal to 2.45 N/C ?
Use 8.85×10−12C2/(N*m2) for the permittivity of free space, and use π=3.14 .

Distance of the point where electric filed is 2.45 N/C is 1.06 m            

Explanation:

We have given charge per unit length, that is liner charge density

Electric field E = 2.45 N/C

We have to find the distance at which electric field is 2.45 N/C

We know that electric field due to linear charge is equal to

, here is linear charge density and r is distance of the point where we have to find the electric field

So

r = 1.06 m

So distance of the point where electric filed is 2.45 N/C is 1.06 m

12000j is work done