Wednesday

July 23, 2014

July 23, 2014

Posted by **Eddie** on Sunday, January 22, 2012 at 8:40pm.

A point charge is placed at each corner of a square with side length a. The charges all have the same magnitude q. Two of the charges are positive and two are negative, as shown in the following figure.

The two positive charges are on top and the two negative charges are on the bottom

What is the magnitude of the net electric field at the center of the square due to the four charges in terms of q and a?

2. Relevant equations

E = k ( q / r^2), k = 9.0*10^9

3. The attempt at a solution

The distance from the middle to one of the charges a/(2^1/2)

The x-components cancel out, leaving only the y-components.

The electric field due to one of the charge to my guess is-

E1sinω = 9.0*10^9 ( 2q / a^2 ) * (1/ (2^1/2))

I assumed that each charge exerts the same electric field so the answer would\ be

4 * 9.0*10^9 ( 2q / a^2 ) * (1/ (2^1/2))

I am not sure what I did wrong.

Thanks so much

**Related Questions**

physics2 - Charges are placed on an equilateral triangle (all angles are equal ...

PHYSICS HELP! - The drawing shows a square, each side of which has a length of L...

Physics - The drawing shows a square, each side of which has a length of L = 0....

Physics - The drawing shows a square, each side of which has a length of L = 0....

physics - The drawing shows a square, each side of which has a length of L = 0....

Physics - The drawing shows a square, each side of which has a length of L = 0....

Physics please clarify - A charge of +1q is fixed to one corner of a square, ...

physics - There are two +q charges and two -q charges on the corners of a square...

physics ..PLEASE HELP ASSIGN DUE SOON :( - A charge is to be placed at the empty...

Physics - Two point charges, one of +3.00 10-5 C and the other -5.00 10-5 C are ...