what is the resistance of dry air?????
Answers
Electrical Resistance is the property of an electrical element to oppose the flow of the current passing through it when a voltage is applied across the element. It is, mathematically, represented as the ratio of the voltage to current.
The flow of electric charge is the cause of electric current. The electric current is due to the flow of electrons. The measurement of electrical system is done by using some properties related to it. These include resistance, electromotive force, and electric charge. The electromotive force is the flow of charges which cause of flow of electric current. It is measured in volts. It’s similar to electrical pressure.
The concept of resistance is given by Ohm in its law. This makes redistrict in the electrical flow in the conductor. All materials have some resistance power natural which makes flow of electricity less. Materials which have low resistance increase electricity flow while materials with greater resistance need electromotive force for electricity flow. Let’s discuss more about the resistance, with its units and problem based on it.
⇒ Electrical Resistance of Dry Air
We know that the resistance depends on the resistivity of the material. The resistivity of the air is 1.3 × 10^16 to 3.3 × 10^16 Ω-m at 200 C. With no ions in the gas its resistance is infinity, so same hold true for air also. So, the resistance of any gaseous material depends on the ion content of that gas.
■█■█■█■█■█■█■█■■█■█■█■█■
■█■█■█■█■█■█■█■■█■█■█■█■
Dry air does not conduct electricity until it electrically breaks down.
It does this in reponse to an electric field, so it is not easy to quote a simple voltage at which it does it - the field strength depends on the shape of electrodes and breakdown can depend on whether an air gap existed before the voltage was applied (so a switch can spark at very low voltages as it is used).
However, the breakdown voltage of dry air is actually around 33,000 V per cm (way above what your previous answerer incorrectly suggested). Its a good job it is this high - a 3 phase mains supply in Europe runs at a peak of 360 V so if it were low we would be in trouble.
■█■█■█■█■█■█■█■■█■█■█■█■
■█■█■█■█■█■█■█■■█■█■█■█■