A charge of 3 C is moved from point:
A(0, −2, −5)
to point:
B(5, 1, 2)
in an electric field:
E = 2x î + 3y² ĵ + 4k̂ N/C
Find the work done in moving the charge from A to B.
Work done by an electric field is:
W = q ∫ E · dr
Given:
E = 2x î + 3y² ĵ + 4k̂
and:
dr = dx î + dy ĵ + dz k̂
Therefore:
E · dr = 2x dx + 3y² dy + 4 dz
Integrating from point A to point B:
∫2x dx = x²
= 5² − 0²
= 25
∫3y² dy = y³
= 1³ − (−2)³
= 1 + 8
= 9
∫4 dz = 4(z₂ − z₁)
= 4(2 − (−5))
= 28
Total potential difference:
25 + 9 + 28 = 62
Since charge q = 3 C:
W = 3 × 62
= 186 J
Final Answer
186 J