The initial setting of cement is primarily due to which of the following?

$A$ space $2.5 \ cm$ wide between two large plane surfaces is filled with oil. The force required to drag a very thin plate of area $0.5 \ m^2$ just midway between the surfaces at a speed of $0.5 \ m/s$ is $1 \ N$. The coefficient of viscosity in $kg/(m \cdot s)$ is:

The gravitational force acting on a particle,due to a solid sphere of uniform density and radius $R$,at a distance of $3 R$ from the centre of the sphere is $F_1$. $A$ spherical hole of radius $(R / 2)$ is now made in the sphere as shown in the figure. The sphere with hole now exerts a force $F_2$ on the same particle. Ratio of $F_1$ and $F_2$ is

In which of the following properties do the two enantiomers of lactic acid differ from each other?

In the extraction of aluminium:
Process $X$: applied for red bauxite to remove iron oxide (chief impurity).
Process $Y$: (Serpeck's process) applied for white bauxite to remove $Z$ (chief impurity). Then,process $X$ and impurity $Z$ are:

If $f(x) = \frac{\cos^2 x + \sin^4 x}{\sin^2 x + \cos^4 x}$ for $x \in R$,then $f(2002) = $