UPSC-2015
1.
Derive the generalized equation for determining the apparent
resistivity from an array of current and potential electrodes . Use
this expression to estimate the apparent resistivity for the above
situation for the current of 1 ampere.
Solution:
Apparent
resistivity (ρa),
(ρa)
= 2*π*(V/I) * [ ( (1/AM) -(1/MB) ) - ((1/AN)-(1/NB) ) ]-1
--(1)
Potential
of M and N is Vp1-p2 = 1.52+2.98
=
3.5 V
Current
(i)= 1 amp
ρa=
2*π*(V/I) * [ ( (1/3) -(1/7) ) - ((1/8)-(1/2) ) ]-1
ρa
= 2*π*(3.5/1) * [ ( (7-3)/ 21 ) - ((2-8)/ 16) ]-1
ρa
= 2*π*(3.5/1) * [ (4/21 ) - (4/16) ]-1
ρa
= 2*π*(3.5) * [ 0.190-0.25 ]-1
ρa
= 2*π*(3.5) * [ 0.44]-1
ρa
= 49.95 Ωm
Therefore,
apparent resistivity (ρa) = 49.95 Ωm
The gravity value measured at the base of a 10 m tall building is 40 mGal, The value at the top of the building ignoring its mass is close to
ReplyDeleteanswer is 43.086m Gal
Deletei posted... please check it once.
how to solve question number 98 from csir net 2015 december set c?
ReplyDeleteI didn't see your comment....sorry for that.
DeleteI posted your problem please check it...
http://gpsurya.blogspot.in/2016/09/csir-net-2015-dec.html
how to solve question number 98 from csir net 2015 december set c?
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