Why is the earth pin in a 3-pin plug the longest and the
thickest?

Answers were Sorted based on User's Feedback



Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / ajay

Resistance =pl/a
where a is "area".

And area is directly propotional to lenght and thickness.

so if the area is greater mean resistance is less.

and resistance is inversly proptional to current.
so it will act as low resistance path for neutral current.

Is This Answer Correct ?    55 Yes 10 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / raj

so that earth ground is connected first due safety.

Is This Answer Correct ?    34 Yes 3 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / tinei munhenzva

Longest:For safety i.e it will be the first connection to
make when you insert a three pin plug.
Thickest: To withstand high fault current in case of an
earth fault without heating up.

Is This Answer Correct ?    25 Yes 2 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / promise mbanga

Agree with all the above, but the main reasons for long
earth terminal are that:

(i) To connect earth first for safety of personnel
(ii) To open the safety locks on the plug for the Live and
Neutral terminals.

The thickness is for making a tight connection and high
carring capacity at the connection point in case of an
earth fault.

Is This Answer Correct ?    20 Yes 2 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / swadesh kumar singh

If there is a short ckt in the plug or line there is some
chance to damage the component or get shock & may fire.so
that earth ground is connected first for safety.

Is This Answer Correct ?    21 Yes 4 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / mukesh jangra

Because when it insert into the socket first of all it
grounded the ckt or equipment so that third pin of 3-pin
plug is longest.Due to this it avoid from shock to person
& give safety.
The reason of thickness of 3rd pin is low resistance.
Because area depends upon length & thickness.If aera is
large means resistance of that body is less.So due to low
resistance the thickness of 3rd pin is large other than.

Is This Answer Correct ?    14 Yes 1 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / dilip kumar

The earth pin in a 3-pin plug the longest and the thickest
because at the time of fault, the fault current must pass
through the earth connection to the ground, the fault
current produced is so many times greater than the normal
current.

Is This Answer Correct ?    10 Yes 6 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / vajresh b

The earth pin is the longest and the thickest pin among the three because in case of a shock it would soon discharge into the earth wire, thus protecting the appliance. Also there is another factor " resistance " large areas have low resistance. And also resistance = pl/ a

Is This Answer Correct ?    3 Yes 0 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / a.baral

earth pin is longest becoz it will touch the ground first
it is for safety purpose
but the thickness case is R=pL/a
a=area
as thickness is more i.e area is more
Resistance inversly propertional to area
area more means resistance is less
current always flow from high resistance path to low
resistance path
fault current pass through that thick point

Is This Answer Correct ?    1 Yes 0 No

Why is the earth pin in a 3-pin plug the longest and the thickest?..

Answer / vidhyashivani

Since resistance is inversely proportional to the area (R = 1A) it provides a low resistive conducting path for the current flowing through it.

The earth wire is made long because it must be long enough to connect to the metal plate placed inside the earth from the appliance.

Is This Answer Correct ?    1 Yes 0 No

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