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Given that an electric field of 3×106V/m3×106V/m is required to produce an electrical spark within a volume of air, estimate the length of a thundercloud lightning bolt.

User Kzorro
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2 Answers

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Final answer:

To estimate a lightning bolt's length, one can utilize the electric field strength of approximately 3×106 V/m, indicative of air's dielectric strength. Multiplying this by the typical voltage for a lightning bolt provides an estimated distance, which can be in the order of 100 meters, though actual lightning paths will vary.

Step-by-step explanation:

Estimating Lightning Bolt Length

The electric field required to produce a spark in air is approximately 3×106 V/m. This value is indicative of the air's dielectric strength—the point at which it can no longer insulate and begins to conduct electricity due to ionization. For lightning to occur, the electric field generated by the charge separation in a thundercloud must exceed this threshold.

The length of a lightning bolt can be estimated using the concept of electric field (E) and the potential difference (voltage, V) required for sparking to occur. The potential difference is obtained by multiplying the electric field strength by the distance over which it is applied (V = E × d). Given that lightning can cause sparks through the air at an electric field of 3×106 V/m, and assuming a typical lightning bolt potential in the order of hundreds of millions of volts, the distance (or length) of a lightning bolt can be considerable, spanning from clouds to the ground.

To estimate this distance, if we consider a potential difference of, say, 300 million volts (which is within the range for a typical lightning bolt voltage), using V = E × d, we find that d = V / E. So, the length d would be around 300 million volts divided by 3×106 V/m, giving a rough estimate of 100 meters for the lightning bolt length. This is a simplification, as the actual path of lightning is not a straight line and the electric field is not uniform along the bolt's length.

User Ollie Edwards
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Answer:

Length, l = 33.4 m

Step-by-step explanation:

Given that,

Electrical field,
E=3* 10^6\ V/m

Let the electrical potential is,
V=10^8\ V

We need to find the length of a thundercloud lightning bolt. The relation between electric field and the electric potential is given by :


V=E* d\\\\d=(V)/(E)\\\\d=(10^8)/(3* 10^6)\\\\d=33.4\ m

So, the length of a thundercloud lightning bolt is 33.4 meters. Hence, this is the required solution.

User Manisha Tan
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