- #1
Dell
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given a cube,each side with a lenth of A, placed at with its back left hand bottom corner at (0,0,0).
find the electric flux passing through the sides if the electric field is
a) E=(-3x)i + (2y)j + (4z)k
b) E=(sin(pi*x/A)i + cos(pi*y/2A)j
for a) since the area of each side is A2, flux=A2*E, since the cube is at the origin, anything on -x,-y,-z will have o value (for x,y,z) and therefore 0 E and so 0 flux
flux=
flux from
right= 2*A*A2 =2A3
left= 2*0*A2 =0
top= 4*A*A2 = 4A3
bottom= 4*0*A2 =0
front= -3*A*A2=-3A3
back= -3*A*A2 =0
for b) i can't see how they got the answers, the answers are all 0 other than ffor the left which they say is
left=-A2
but as far as i can tell, the left flux is [cos(pi*y/2A)j * A2 ] cos(pi/2)=0 so i don't see how they come to this??
hope i am doing this right, really not sure, any help appreciated
find the electric flux passing through the sides if the electric field is
a) E=(-3x)i + (2y)j + (4z)k
b) E=(sin(pi*x/A)i + cos(pi*y/2A)j
for a) since the area of each side is A2, flux=A2*E, since the cube is at the origin, anything on -x,-y,-z will have o value (for x,y,z) and therefore 0 E and so 0 flux
flux=
flux from
right= 2*A*A2 =2A3
left= 2*0*A2 =0
top= 4*A*A2 = 4A3
bottom= 4*0*A2 =0
front= -3*A*A2=-3A3
back= -3*A*A2 =0
for b) i can't see how they got the answers, the answers are all 0 other than ffor the left which they say is
left=-A2
but as far as i can tell, the left flux is [cos(pi*y/2A)j * A2 ] cos(pi/2)=0 so i don't see how they come to this??
hope i am doing this right, really not sure, any help appreciated