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# electricity questions watch

1. It's estimated the average electric charge carried din a lightning flash is 5C if the PD between ground and surface is 600 MV.

In a typical thunderstorm lightning flashes strike the ground at 3 minute intervals. Over the whole surface of the Earth the total current carried this way between the atmosphere and the ground averages 1800A. Estimate the average no. Thunderstorms taking place at any one time?

I've found energy transferred in one flash for part a) of the question and got 4x10^9. I'm not sure how to approach this bit.

Cheers
2. Energy=QV
So 5x600x10^6=3x10^9.
3. (Original post by Pricilla kashfi)
Energy=QV
So 5x600x10^6=3x10^9.
The question isn't asking for energy?
4. (Original post by BDunlop)
It's estimated the average electric charge carried din a lightning flash is 5C if the PD between ground and surface is 600 MV.

In a typical thunderstorm lightning flashes strike the ground at 3 minute intervals. Over the whole surface of the Earth the total current carried this way between the atmosphere and the ground averages 1800A. Estimate the average no. Thunderstorms taking place at any one time?

I've found energy transferred in one flash for part a) of the question and got 4x10^9. I'm not sure how to approach this bit.

Cheers
I=Q/t for each lightning bolt.

Then do total current divided by current for 1 lightning bolt to get total number of lightning bolts.
5. (Original post by Shaanv)
I=Q/t for each lightning bolt.

Then do total current divided by current for 1 lightning bolt to get total number of lightning bolts.
Okay, cheers. I wasn't sure what value of t to use. I was thinking how long it takes for 1 bolt to produce 5C charge which we don't know, but I presume t is the 'time between 2 strikes' if you can see what I'm saying..
6. (Original post by BDunlop)
Okay, cheers. I wasn't sure what value of t to use. I was thinking how long it takes for 1 bolt to produce 5C charge which we don't know, but I presume t is the 'time between 2 strikes' if you can see what I'm saying..
I would use 3 minutes, as 5C of charge is delivered every 3 minutes. This is the same as the time between strikes.

Remember to convert to seconds👊🏾

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