For the charge configuration in case C of D2L question 1 with q = 1 nC and triangle side length of 2 cm, calculate the following:
a)The electric field at the center of the triangle.
b)The electric potential at the center of the triangle.
c)The energy of the system of three point charges.
d)Calculate the work done to bring a +0.5 nC point charge from infinity to the center of the triangle.
e)Calculate the force on a +0.5 nC point charge placed at the center of the triangle.
a) E = (kQ)/r^2
b) Ep(tot) = k( (q1/r)+(q2/r) ...)
d) U(tot)=k((q1q2/r)+(q3q4/r)...) and U = -W
e) F = k(abs(q1)abs(q2)/r^2)
The Attempt at a Solution
a) For a I made a force diagram similar to this:
I came up with: 412764 n/c x(hat) + 257978 n/c y(hat)
The angle I used for theta was 30* and the distance I came up with for r was .0132 m.
b) For b I calculated that V = 3405.3 volts
c) This question was a bit confusing I made the assumption that by energy my teacher meant for me to take V and divide out the charge but I could definitely be wrong. That being said I came up with a value of 6.8x10^11 Joules, which seems high to me.
d) I am also confused about this question. I am still a bit hazy on the relationship between potential energy and work. What I decided to do was calculate the total potential energy U for the four particle system then I tacked on a negative sign and called it the work... here is the number I came up with: W = -1.7x10^-6 Joules.
e) For e I made a similar force diagram that I made for a. I came up with a total force of:
2.06x10^-4 N x(hat) - 1.3x10^-4 N y(hat)
After finishing this question I feel as though I might be close on a few of the answers but I am still not confident on most of them. Any help would be appreciated, thanks.
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