If $\frac{ax - 1}{(1 - x + x^2)(2 + x)} = \frac{x}{1 - x + x^2} - \frac{1}{2 + x}$,then $a = $

The value of $a$ for which the equations $x^3+ax+1=0$ and $x^4+ax^2+1=0$ have a common root is

When the engine is switched off,a vehicle of mass $M$ is moving on a rough horizontal road with momentum $p$. If the coefficient of friction between the road and the tyres of the vehicle is $\mu_k$,what is the distance travelled by the vehicle before it comes to rest?

When a liquid is heated in a copper vessel, its coefficient of apparent expansion is $6 \times 10^{-6} /{ }^{\circ} C$. When the same liquid is heated in a steel vessel, its coefficient of apparent expansion is $24 \times 10^{-6} /{ }^{\circ} C$. If the coefficient of linear expansion for copper is $18 \times 10^{-6} /{ }^{\circ} C$, what is the coefficient of linear expansion for steel?

In order to determine whether variations of a character in a population were genetically controlled,the most appropriate procedure will be to

$A$ particle is projected from a point at an angle $\theta$ with the horizontal direction. At any time $t$,if $p$ is the linear momentum,$y$ is the vertical displacement,and $x$ is the horizontal displacement,which of the following graphs does $NOT$ represent the variation of kinetic energy $(KE)$ of the particle?