Which of the following displacement $(X)$ time graphs is not possible?

The acceleration $a$ (in $ms ^{-2}$ ) of a body, starting from rest varies with time $t$ (in second) according to the relation $a=3 t+4$. The velocity of the body starting from rest at time $t=2 s$ will be $........ms ^{-1}$

Which of the following velocity-time graphs is physically not possible?

The graph of displacement v/s time is given below Its corresponding velocity-time graph will be

Two particles $A$ and $B$ start from rest and move for equal time on a straight line. Particle $A$ has an acceleration of $2\,m / s ^2$ for the first half of the total time and $4\,m / s ^2$ for the second half. The particle $B$ has acceleration $4\,m / s ^2$ for the first half and $2\,m / s ^2$ for the second half. Which particle has covered larger distance?

The displacement of a particle moving in a straight line depends on time as $x=\alpha t^3+\beta t^2+\gamma t+\delta$.The ratio of initial acceleration to its initial velocity depends