In case of uniform circular motion which of the following physical quantity do not remain constant

For a particle in uniform circular motion, the acceleration $\vec a$ at a point $P(R,\theta)$ on the circle of radius $R$ is (Here $\theta$ is measured from the $x-$ axis)

Certain neutron stars are believed to be rotating at about $1\,rev/\sec $. If such a star has a radius of $ 20\, km$, the acceleration of an object on the equator of the star will be

A body is moving with constant speed, in a circle of radius $10 m$. The body completes one revolution in $4 s$. At the end of $3 rd$ second, the displacement of body (in $m$ ) from its starting point is:

A particle starting from rest, moves in a circle of radius $r$. It attains a velocity of $\mathrm{V}_{0} \;\mathrm{m} / \mathrm{s}$ in the $\mathrm{n}^{\text {th }}$ round. Its angular acceleration will be

A tube of length $L$ is filled completely with an incompressible liquid of mass $M$ and closed at both the ends. The tube is then rotated in a horizontal plane about one of its ends with a uniform angular velocity $\omega $. The force exerted by the liquid at the other end is