Electrostatics Question 713
Question: Point charge q moves from point P to point S along the path PQRS (as shown in fig.) in a uniform electric field E pointing co-parallel to the positive direction of X-axis. The coordinates of the points P, Q, R and S are (a, b, 0), (2a, 0, 0), (a, -b, 0) and (0, 0, 0) respectively. The work done by the field in the above case is given by the expression
Options:
A) $ qEA $
B) $ -qEA $
C) $ qEA\sqrt{2} $
D) $ qE\sqrt{[ {{( 2a )}^{2}}+b^{2} ]} $
Show Answer
Answer:
Correct Answer: B
Solution:
[b] $ w=\vec{F}.\vec{s}=Eq\hat{i}.( -a\hat{i}-b\hat{j} )=-Eqa $
