The observed standard penetration test value in a deposit of fully submerged sand was 45 at a depth of 6 m. The average submerged unit weight of the soil is 9.7 kN/m3. The corrected N value is : (consider only overburden correction) (a) 43.76 (b) 67.14 (c) 54.63 (d) 58.95

43.54

Explanation:

Effective overburden pressure  will be

Overburden correction is given by

Where and are effective overburden pressure and overburden correction

Substituting the value of overburden pressure then

Taking hammer efficiency of 0.8,  drill rod length correction factor of 0.9 and  borehole correction factor of 1.05 then corrected SPT value will be

current and voltage can both be different in different parts of a circuit so it matters where you place the ammeter and voltmete