What is the cause of vibration of telephone wires in a strong wind blowing across the wire?

Imagine a high wind blowing through telephone wires. As it skims across the top and bottom of a wire, the wind becomes unstable. These eddies in the wind in turn set up patterns of changing pressure in the air ahead of the wire.

Why are conductors for high voltage transmission lines suspended from towers?

ANSWER: Increase the clearance from ground.

Does wind pressure reduce corona effect?

Which of the following statement is correct? (D) Wind pressure and ice on conductors together improve regulation of power transmitted….

Why does wind whistle in winter?

As the wind passes through and around their branches and leaves, they cause those objects to move back and forth. This movement creates vibrations in the air, known as longitudinal pressure waves, which can travel to your ears as soft rustling or louder whooshing sounds.

Why does the wind whistle around my house?

In most cases, whistling is the result of wind passing through a slight gap in the window – and anything that can be done to close that gap will help to eliminate the whistling. Filling hollow spaces and securing things into position will help reduce the noise – so be sure to do so.

When conductor carries more current on the surface as compared to core it is due to?

Detailed Solution. The tendency of alternating current to concentrate near the surface of a conductor is known as skin effect.

Which support for overhead transmission line has the least life?

Wooden poles: It is one of the cheapest types of line supports and used for lines where spans are short, and tension is low. It has very less life.

Which is the topmost conductor in the HV transmission?

A guard wire or earth wire is the top most conductors in high voltage transmission lines. It is used mainly to protect lines from lightning. If in case lightning struck then it carries the excessive current inrush to ground.

Why do transmission lines carry such high voltages?

The primary reason that power is transmitted at high voltages is to increase efficiency. The higher the voltage, the lower the current. The lower the current, the lower the resistance losses in the conductors. And when resistance losses are low, energy losses are low also.

How does wind affect the overhead line tower?

Owing to its tall structure, the overhead line tower is usually subjected to strong winds. As well as causing vibration in the conductors, high wind speeds can also cause the conductors to move closer to or away from the tower body [1], [2].

How does wind affect the conductors in a wind turbine?

As well as causing vibration in the conductors, high wind speeds can also cause the conductors to move closer to or away from the tower body [1], [2]. Both the insulator swing, as well as the conductor swing, reduces the clearances.

What causes a tower to change its shape?

Most overhead transmission lines are exposed to some natural phenomena such as wind, temperature and humidity, all of which can, directly or indirectly, cause a change in the tower top geometry and clearances. Owing to its tall structure, the overhead line tower is usually subjected to strong winds.

How does wind velocity affect tower structural design?

The wind velocity is considered as the basis for tower structural design. The wind velocity may lead to the ultimate load, which may stress the structure to its maximum strength capacity. In addition, some other parameters should also be taken into consideration.