Please show the FORMULA first and then solve for the values. THE PROBLEM Imagine
ID: 1574270 • Letter: P
Question
Please show the FORMULA first and then solve for the values.
THE PROBLEM Imagine a square where every side is L-9.5 cm in length. Attach a charge of q-77 HC at one of the corners. At each of the other three corners, attach a charge of -2q Calculate the potential energy stored in this configuration of charges. PAPER SOLUTION Solve the problem on paper first, including all four IDEA steps. You will become a better physicist that way! Have you finished your paper solution already? Oyes no INTERPRET Identify all of the true statements. If we bring the four charges one-at-a-time from infinity to their locations, then A. the work to bring the second charge equals the change in potential energy between the 1st and 2nd charges. B. it takes no work to bring the first charge. C. the work to bring the second charge equals the electric potential between the 1st and 2nd charges. E. None of the above. DEVELOP Derive an algebraic expression for the potential energyExplanation / Answer
a = length of the side of the square = 9.5 cm = 0.095 m
r = length of the diagonal = sqrt(2) a = sqrt(2) (0.095) = 0.134 m
Q = charge at other three corners = - 2 q = - 154 x 10-6 C
q = charge at one corner = 77 x 10-6 C
electric potential energy of the system is given as
U = k q Q/a + k q Q/a + k q Q/r + k Q2/a + k Q2/r + k Q2/a
U = 2 k q Q/a + k q Q/r + k Q2 (1/r + 1/a)
U = 2 (9 x 109) (77 x 10-6) (- 154 x 10-6)/(0.095) + (9 x 109) (77 x 10-6) (- 154 x 10-6)/(0.134) + (9 x 109) (- 154 x 10-6)2 (1/(0.134) + 1/(0.095))
U = 796.4 J