- #1
Moxin
- 24
- 0
*sigh*, Another long semester of physics...
Anyways, here we go ! Here's the problem:
Calculate the magnitude of the electric field at the center of a square with sides 27.3 cm long if the corners, taken in rotation, have charges of 1.10 microC, 2.20 microC, 3.30 microC, and 4.40 microC (all positive).
Using Pythagorean's thereom I find the radius to all these Point Charges to be 0.193040 m
So then I try plugging All this info in the Eq'n for finding Electric field magnitude and direction.. E = kQ/(r^2) where k = 9.0*10^9
At first, I tried E = (k/r^2)(Q1 + Q2 + Q3 + Q4)
and got 2660000. Which, apparently, is wrong.
From looking at the study guide and the book, I'm guessin I'm leaving out some very important trigonometric calculations necessary to go further.. So I decided to calculate the electric field produced by each point charge at the center
E1 = 265668
E2 = 531337
E3 = 797005
E4 = 1062674
Then I Broke Each into their Components by arbitrarily assigning them corners of a square
E1x = 187855
E1y = -187855
E2x = -375712
E2y = -375712
E3x = -563568
E3y = 563568
E4x = -751424
E4y = 751424
Then I Added up the components, and got -1 for the sum of x, 751424 for the sum of y. I then applied the pythagorean theorem and rejoiced in excitement as I got the wrong answer.. again.. after all that. Can someone help me out here ? ?
Anyways, here we go ! Here's the problem:
Calculate the magnitude of the electric field at the center of a square with sides 27.3 cm long if the corners, taken in rotation, have charges of 1.10 microC, 2.20 microC, 3.30 microC, and 4.40 microC (all positive).
Using Pythagorean's thereom I find the radius to all these Point Charges to be 0.193040 m
So then I try plugging All this info in the Eq'n for finding Electric field magnitude and direction.. E = kQ/(r^2) where k = 9.0*10^9
At first, I tried E = (k/r^2)(Q1 + Q2 + Q3 + Q4)
and got 2660000. Which, apparently, is wrong.
From looking at the study guide and the book, I'm guessin I'm leaving out some very important trigonometric calculations necessary to go further.. So I decided to calculate the electric field produced by each point charge at the center
E1 = 265668
E2 = 531337
E3 = 797005
E4 = 1062674
Then I Broke Each into their Components by arbitrarily assigning them corners of a square
E1x = 187855
E1y = -187855
E2x = -375712
E2y = -375712
E3x = -563568
E3y = 563568
E4x = -751424
E4y = 751424
Then I Added up the components, and got -1 for the sum of x, 751424 for the sum of y. I then applied the pythagorean theorem and rejoiced in excitement as I got the wrong answer.. again.. after all that. Can someone help me out here ? ?