When the plastic limit of a soil is greater than the liquid limit, then the plasticity index is reported as
A. negative
B. zero
C. non-plastic (NP)
D. 1
Answer: Option C
Solution(By Examveda Team)
Option A: negativeThis option is incorrect. The plasticity index cannot be negative. It is either zero or non-plastic (NP) in such cases.
Option B: zero
This option is incorrect. Zero is used when the plastic limit is equal to the liquid limit, not when it is greater.
Option C: non-plastic (NP)
This is the correct option. When the plastic limit exceeds the liquid limit, the soil is considered non-plastic, and the plasticity index is reported as NP.
Option D: 1
This option is incorrect. The plasticity index is not arbitrarily set to 1 in any standard soil mechanics context.
In conclusion, the correct answer is Option C: non-plastic (NP), as this correctly represents the condition when the plastic limit is greater than the liquid limit in soil mechanics.
This Question Belongs to Civil Engineering >> Soil Mechanics And Foundation
Please read it with full concentration and try to undrestand it, when plastic limit of a soil is greater than the liquid limit, then the (PLASTICITY INDEX) is reported as (zero) and the (SOIL) is termed as Non-plastic. The answer should be zero as the question is not asking about soil condition rather it is asking about ranges of the soil in which it is categorised. So the answer is zero and in such case the soil is considered as non plastic when the plastic limit is greater than liquid limit. If you are still confused,plz resort to testbook.com. write this same question on Google with testbook in the end and you will get your answer.
This parameter cannot be negative if plastic limit, in some exceptions, is larger than the liquid limit, it is considered to be zero and soil is considered non-plastic
Ip=WL-WP
IF WP IS GREATER THAN WL IT SHOWS NEGATIVE
HENCE OPTION A IS CORRECT