- #1
Maria H
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I feel like a stupied girl. :(
It think it's not very hard, but I have to have the correct answear before i send it to my school.
We sometimes exposed to electric fields. To determine whether there is a risk of flashover is a rule of thumb which states that the sparks will switch if it is larger than the field strength of 1kV per mm, ie 1MV/m.
a) How big is the largest electric field between two leaders in a 230V-power line (peak voltage is 324V)? We assume that the distance between conductors is 2mm. Reply with a rounded integer. Answear in kV/m
b) If a person stands on a railway-wagon, an accident can happen if you come too close to the lead. If the voltage is 16kV, at which distance can a spark jump over and kill a person? The authority has a rules that says 270mm between the leaders at that voltage. Then you have gardening has objected to the management of moist air, etc.. Reply with a rounded integer.
c) If the insulation around a conductor to a coffee machine is damaged, at what distance from the leader can get a spark to turn over to a sink? Reply with two decimal places.
E=U/d
a) 324/0.002 =162000 =162kV/m I'm pretty right here :/
b) 16kV/1(kV/mm) = 16 mm
16mm according to the rule of thumb 1kV per mm. I don't see how I should take the rule of 270mm into considiration. It's obvioulsy a better distans..
c) 0.230V/1(kV/mm) = 0.23mm
Cheers/Maria
It think it's not very hard, but I have to have the correct answear before i send it to my school.
Homework Statement
We sometimes exposed to electric fields. To determine whether there is a risk of flashover is a rule of thumb which states that the sparks will switch if it is larger than the field strength of 1kV per mm, ie 1MV/m.
a) How big is the largest electric field between two leaders in a 230V-power line (peak voltage is 324V)? We assume that the distance between conductors is 2mm. Reply with a rounded integer. Answear in kV/m
b) If a person stands on a railway-wagon, an accident can happen if you come too close to the lead. If the voltage is 16kV, at which distance can a spark jump over and kill a person? The authority has a rules that says 270mm between the leaders at that voltage. Then you have gardening has objected to the management of moist air, etc.. Reply with a rounded integer.
c) If the insulation around a conductor to a coffee machine is damaged, at what distance from the leader can get a spark to turn over to a sink? Reply with two decimal places.
Homework Equations
E=U/d
The Attempt at a Solution
a) 324/0.002 =162000 =162kV/m I'm pretty right here :/
b) 16kV/1(kV/mm) = 16 mm
16mm according to the rule of thumb 1kV per mm. I don't see how I should take the rule of 270mm into considiration. It's obvioulsy a better distans..
c) 0.230V/1(kV/mm) = 0.23mm
Cheers/Maria