Electrostatics Question 411
Question: The displacement of a charge Q in the electric field $ E=e _{1}\hat{i}+e _{2}\hat{j}+e _{3}\hat{k} $ is $ \hat{r}=a\hat{i}+b\hat{j} $ . The work done is [EAMCET (Engg.) 2000]
Options:
A) $ Q(ae _{1}+be _{2}) $
B) $ Q\sqrt{{{( ae _{1} )}^{2}}+{{( be _{2} )}^{2}}} $
C) $ Q(e _{1}+e _{2})\sqrt{a^{2}+b^{2}} $
D) $ Q(\sqrt{e _{1}^{2}+e _{2}^{2})}\ (a+b) $
Show Answer
Answer:
Correct Answer: A
Solution:
By using $ W=Q(\overrightarrow{E}.\Delta \overrightarrow{r}) $
therefore $ W=Q[(e _{1}\hat{i}+e _{2}\hat{j}+e _{3}\hat{k}).(a\hat{i}+b\hat{j})]=Q(e _{1}a+e _{2}b) $
