In a certain region of space the electric field is constant in direction (say horizontally, in the x direction), but its magnitude decreases from E=560 N/C at x=0 to E = 410 N/C at x=30m. Determine the charge within a cubical box of side l = 30m, where the box is oriented so that four of its sides are parallel to the field lines.
The answer to this is -1.2 micro C. I have now idea how they got this answer. Any help is appreciated.
2006-09-04 00:48:16 · 1 answers · asked by Anonymous in Science & Mathematics ➔ Physics
I think I may have gotten it.
I took the 560 * 30^2 * 8.85 *10^-12 = 4.4606 * 10^-6
Then I took
410 * 30^2 * 8.85 *10^-12 = 3.26565*10^-6
Then I subtracted both the answers and got the 1.2 micro C....Is this correct or just a coincidence?
2006-09-04 01:08:50 · update #1
Not a coincidence, you do have the math right, but remember to subtract the initial value from the final value to give a negative answer: - 1.2 microC.
2006-09-04 01:25:45 · answer #1 · answered by Richard 7 · 79⤊ 0⤋