which occurs first lightening or thunder?

Answer 1

Lightning travels at about half the speed of light, thunder travels at the speed of sound. Lightning occurs first.
In addition to the audible sound, (thunder) which has a spectral maximum at about 100 Hz, there is also an infrasonic signal of equivalent strength, down to periods of about 1 second. The main influence on the received sound is refraction in the atmosphere. Since the air is cooler above, sound travels more slowly there. A vertical wavefront will be retarded in its upper parts relative to its lower parts, and since the energy travels normally to the wavefronts, it will tend to rise. It is generally said that thunder is not audible beyond 25 km (16 miles), which is largely due to this effect. The speed of sound at normal temperatures is roughly 1000 ft/s or 340 m/s, so that by timing the interval between lightning and thunder one can estimate the distance of the lightning stroke. This is a very well-known experiment that was the first one used for the accurate determination of the speed of sound in the 17th century.

However, the lightning speed is normally no more than half the speed of light, usually substantially less.
The process that creates a lightning stroke is not light transfer, but is the transfer of electrical energy (charge) through the air. Much like an electrical cable, the air, even though it is ionized, has some resistance to charge transfer. The speed of the stroke is impeded by having to transfer the energy from molecule to molecule along the way, in the process literally exploding the molecules into atoms.

Answer 2

lightning occurs first even though you dont always see it.

Electricity
Electrical discharges occur through the atmosphere between the P and N regions of a cloud, between two clouds, and, of course, between cloud and ground. The most is known about this latter discharge, since its path is mostly visible, while the others are hidden. There are even discharges between the tops of a thundercloud and the ionosphere, which were suspected for years, but now have been definitely identified. The mechanism of breakdown between two regions kilometers apart seems quite different from breakdown in the laboratory, but the processes are essentially the same, differing only in scale.

For cloud-to-ground strikes, which make up perhaps 20% of all lightning discharges, the process usually starts at the edge of the N region where the local field is great enough to enable the electrons to ionize air molecules, which is happening all the time, in which electron avalanches create a quiet, nonluminous Townsend discharge. If the field is a little stronger, a self-sustaining pulse of ionization, like the beginning of a corona discharge, takes place and a luminous finger of plasma darts forward until it is stopped by the weakening of the field. Then, the copious electrons at the beginning of the discharge fill out the conducting path and cause the field to strengthen at the head of the discharge. The light radiated from the discharge ionizes molecules around the head of the discharge, making the establishment of a path easier. With the field re-established, the discharge chooses one of these directions and darts forward again. The narrow path of the discharge exits the cloud and becomes visible below it. The path is irregular because of the random choice of direction at each step, and may even branch. This is called the stepped leader. It is moderately luminous, but not greatly so, and moves in the direction of the field a few metres at a time. The head of the discharge is brighter than the narrow conducting path behind it where electrons arrive to charge the path to a high negative potential. The current in the stepped leader is on the order of a hundred amperes.

The field between the header and the ground becomes stronger as the distance decreases, and usually a positive discharge, with the electrons leaving its base, comes up to meet it. When the two columns join, there is suddenly a conducting path between the N region in the cloud and the positively charged earth, with perhaps a million volts potential difference. Now the main stroke occurs, with kiloamperes of current, neutralizing the potential difference, and heating the conducting path to thousands of K. This, in effect, discharges the capacitor whose plates are part of the N region, and the earth, through the inductance of the filamentary conducting path. If there is still energy to be discharged, a new probe may search its way out of the N region towards the earth, using the previous path if not too much time has elapsed and the ionization has decayed. When this dart leader, which moves much faster than the previous stepped leader that was exploring virgin territory, reaches the earth, it is followed by another main stroke. This may be repeated several times. There is one case where 26 successive strokes were counted. If a second or so has elapsed, however, a new stepped leader must discover a new path.

A similar process occurs for intracloud and cloud-to-cloud strokes, where usually the electron-rich N regions initiate the leaders. Apparently, there can be positive leaders as well, originating in the P regions, but the negative leaders seem to predominate. The usual lightning stroke lowers coulombs of negative charge to the ground.


Thunder
The heated air in the conducting channel expands violently and abruptly, to a pressure of about 10 atm, creating a cylindrical shock wave that decays into a sound wave at a distance of a few metres from the lightning channel. The sound that is observed depends on the distance from the stroke. Close to the stroke, the powerful result of the shock wave is heard, which makes a sharp bang of disconcerting strength, a "thunderclap." Farther away, this clap passes over our heads due to refraction by the lapse rate, and we hear the sound from the length of the channel, which arrives according to its distance from us. The result is a rumble or roll lasting several seconds. Acoustic radiation from the cylindrical channel is predominantly at right angles to the channel.

Answer 3

Lightening comes 1st, because the electrical charge caused by lightening creats thunder

Answer 4

The sound of thunder is the wave that is created when lighting rapidly heats the surrounding air. Thus, thunder starts very quickly after lightning, but there is a delay between thunder and lightning because light travels faster than sound.

Answer 5

Lightening.

Answer 6

They occur at the exact same time

Except light travels fast than sound we think that lightening is first

Answer 7

Lightning causes the thunder.

Answer 8

Lightning - the sudden heating of the air column is what produces the thunder.

Answer 9

Lightning

Answer 10

they happen simultaneously but of course light travels faster than sound so you see the lightning first unless it happens right next to you then they occur at precisely the same moment.