Answer Posted / ratan soni
If you remember a technical term.......Reflection
coefficient>> ideally it should be = 1 but practically its
between 0.9 and 0.95
Now , earthing grid is laid down in the ground beneath the
soil in the yard. This grid is in the form of rectangle
,triangle,square shaped or trapezoidal shape .....i.e. as
per the space available and resistivity of the soil.
Now the earthing current which flows down into the earth
through the earthing plates into the grid has the tendency
to flow upwards to the surface bcoz the surface resistivity
is less than the ground...this could be dangerous for the
staff working in the yard...so to reflect back this current
back to the earth the stones are being laid down....thus
increasing the resistiviy of the surface.
| Is This Answer Correct ? | 16 Yes | 3 No |
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