Consider a charged capacitor made with two square plates of side length $L$, uniformly charged, and separated by a very small distance $d$. The EMF across the capacitor is $\xi$. One of the plates is now rotated by a very small angle $\theta$ to the original axis of the capacitor. Find an expression for the difference in charge between the two plates of the capacitor, in terms of (if necessary) $d$, $\theta$, $\xi$, and $L$. 
	
	Also, approximate your expression by transforming it to algebraic form: i.e. without any non-algebraic functions. For example, logarithms and trigonometric functions are considered non-algebraic. Assume $ d << L $ and $ \theta \approx 0 $. 
	
	$\emph{Hint}$: You may assume that $ \frac {\theta L}{d} $ is also very small. 

[i]Problem proposed by Trung Phan[/i]

[hide="Clarification"]
There are two possible ways to rotate the capacitor. Both were equally scored but this is what was meant: [asy]size(6cm);

real h = 7;
real w = 2;

draw((-w,0)--(-w,h));
draw((0,0)--(0,h), dashed);
draw((0,0)--h*dir(64));
draw(arc((0,0),2,64,90));
label("$\theta$", 2*dir(77), dir(77));
[/asy]
[/hide]