GATE-2018 (24) :Wyllie – Time average equation

CSIR-NET 2016

23. The density of a quartz- magnetite rock with 30% magnetite is around

A) 3.0 g/cc             B) 3.3 g/cc                   C) 4.0 g/cc        D) 5.0 g/cc

Answer :B

 Explanation:

Quartz density= 2.6 g/cc

Magnetite density=5.15 g/cc

In quartz-magnetite rock contain 30% magnetite means, remaining 70% rock contain quartz

 therefore,  

 Density= (magnetite density * concentration) + (quartz density * concentration)

             =(0.3* 5.15)+ (0.7* 2.6)

             =3.3 g/cc