Air becomes conducting when the electric field strength in a region exceeds 3x106 V/m. if a spark jumps between a charged object and a grounded object when the two objects are 10 cm apart, what is the potential difference between the two objects? If a lightning strike is 4x103 m long, what is the potential difference which causes this lightning strike?
To find the potential difference between the two objects when a spark jumps, we can use the formula:
Potential Difference = Electric Field Strength x Distance
Given that the electric field strength required for air to become conducting is 3x10^6 V/m and the distance between the two objects is 10 cm (or 0.1 m), we can substitute these values into the formula:
Potential Difference = (3x10^6 V/m) x (0.1 m)
= 3x10^5 V
Therefore, the potential difference between the two objects is 3x10^5 V.
Now, to calculate the potential difference that causes a lightning strike, we can use a similar approach. The length of the lightning strike is given as 4x10^3 m.
We know that the electric field strength required for air to become conducting is 3x10^6 V/m. So, we can use the formula:
Potential Difference = Electric Field Strength x Distance
Potential Difference = (3x10^6 V/m) x (4x10^3 m)
= 12x10^9 V
Therefore, the potential difference that causes the lightning strike is 12x10^9 V.