NEET-XII-Physics

P1 year:2019

with Solutions - page 2
  • #36
    Two parallel infinite line charges with linear
    charge densities +``\lambda`` C/m and -``\lambda`` C/m are
    placed at a distance of 2R in free space. What
    is the electric field mid-way between the two
    line charges?
    (1) Zero
    (2)``\frac{2\lambda}{\pi\varepsilon _0 R}`` N/C
    (3)``\frac{\lambda}{\pi\varepsilon _0 R}``N/C
    (4)``\frac{\lambda}{2\pi\varepsilon _0 R}``N/C
    digAnsr:   3
    Ans : ( 3 )
    Sol. -
    -
    -
    -
    -
    -
    -
    -
    -
    -
    +
    +
    +
    +
    +
    +
    +
    +
    -+
    (1)(2)
    R E2
    E
    1
    X-X
    Electric field due to line charge (1)
    =
    
    1
    0
    ˆE i N /C
    2 R
    Electric field due to line charge (2)
    =
    
    2
    0
    ˆE i N /C
    2 R
    = +
    net 1 2
    E E E
    =
     +
     
    0 0
    ˆ ˆi i
    2 R 2 R
    =

    
    0
    î N /C
    R