Question

The electirc field in a region is given by `vecE = (2x hati + 4y hatj) xx 10^(6) N//C` where `x` and `y` are in meters. `A 1 muC` charges particle is moved from origin to coordinates `(2m, 4m)` first along the y-axis and then along the x-axis. The work done by the elctric field is:
A. `-36 J`
B. `+36 J`
C. `0`
D. `16 J`

Answer 1

Correct Answer - B
Work done in moving from `0` to `A`
`W_(QA) = underset(0)overset(4)int 4ydy = 32J`
Work done in moving from `A` to `B`
`W_(AB) = underset(0)overset(2)int 2xdx = 4J`
`:.` Net work done `= 36 J`