The value of $\lambda$ such that $\lambda x^2-10 x y+12 y^2+5 x-16 y-3=0$ represents a pair of straight lines is:

The horizontal and vertical displacements of a projectile at time $t$ are $x=36 t$ and $y=48 t-4.9 t^2$,respectively. Initial velocity of the projectile in $m/s$ is

The half-life of $Ra^{226}$ is $1620$ years. Calculate the number of atoms that decay in one second in $1 \ g$ of radium (Avogadro number $= 6.023 \times 10^{23}$).

Cardiac muscle fibers differ from skeletal muscle fibers in that they are -

If $g$ is the acceleration due to gravity on the earth's surface,the gain in the potential energy of an object of mass $m$ raised from the surface of the earth to a height equal to the radius $R$ of the earth is

In a reaction $N_{2(g)} + 3H_{2(g)} \to 2NH_{3(g)}$,the rate of appearance of $NH_3$ is $2.5 \times 10^{-4} \, mol \, L^{-1} \, s^{-1}$. The rate of reaction and rate of disappearance of $H_2$ will be (in $mol \, L^{-1} \, s^{-1}$):