The reason why power lines are dimmed

Power lines are dimmed when installed on electric poles because they are mass and attracted by the gravity of the Earth.

Suppose we hang two ends of a wire into two horizontal points. The sum of the forces on the wire must be equal to the vector, because it is in equilibrium. This means that the sum of forces at the ends of the wire must be equal to the magnitude of the gravitational force. Gravity affects the power cord because it has mass, according to Wired.

Wires when hanging on electric poles are always dimmed.(Photo: Wired).

So how do the forces act on a small part of the wire? Let us imagine being able to isolate a small piece of wire near the center, where the power cord sags the most. Because this part of the wire is also in equilibrium, the total force vector acts on the piece of wire with the vector.

We see that there are all three forces acting on the power line. Gravity pulls downward, with intensity depending on the value of the gravitational field and the amount of wire. The other two forces are the tension T of the rope, located at the tangent position to the wire hammock.

The electric wire is affected by two T forces and the Earth's gravity.(Photo: Wired).

Seeing this, you will understand why the wire must be dimmed. Because the wire has a mass and gravity pulls it down, there must be a tension force T upwards to keep the power cord stationary. A horizontal electric wire will not have upward force to balance the gravity downward.

We can increase the tension of the wire to reduce its deflection. But the power cord will never be completely horizontal.