Answer 1:
Electrical power lines can attract and repel
each other, but the amount of force involved is
very small under most common conditions. You
probably know that two currents in the same
direction attract each other, and currents in
opposite directions repel. The magnitude of this
force over a wire of length L (assuming the
currents in each wire are equal) is F=
mu*I^{2}*L/(2*pi*d) where: mu is
the permeability of free space
(1.26*10^{6}
Newtons/Amp^{2}) I is the current in
the two wires L is the length of the wire
(meters) d is the distance between the wires
(meters) F is the resulting force in Newtons,
which can be converted to pounds of force by
multiplying by 0.225.
To take an example
typical of a high power kitchen appliance like a
water kettle, the current in the two wires going
to the outlet in the wall is about 10A, and the
distance between them is about 5mm. Over a 1
meter wire length the force is only 0.004 Newtons,
which is a bit under onethousandth of a pound, so
it's very small! The currents involved in
utility power lines are larger, but also keep in
mind that the power company uses a step up
transformer so that the power lines are at a much
higher voltage than the 110V or 220V that we use
inside the house. The power is equal to voltage
times current. This means that even though a
single wire may power several blocks worth of
houses, the current in the wire is less than the
total current going into each house. The wires
are also much further apart than in the previous
example, and the force is largest for wires closer
together. There may be a tiny force between the
wires of utility power lines, but it's small
enough that we can usually ignore it, the utility
poles will keep the wire from moving much.

Answer 2:
Good question. First off, electrical lines
are insulated, which may alleviate the effect
somewhat. More importantly, though, electrical
power lines carry alternating current  the
current isn't going in one direction all the time,
and therefore neither is the force. Last, and most
important of all, while the VOLTAGE in electrical
power lines is tremendous, the CURRENT actually
ISN'T very large, so there isn't much force to
begin with.
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