Two gases $A$ and $B$ having the same volume,effuse through an orifice in $30 \ min$ and $10 \ min$ respectively. The molar mass of $A$ is $162$. The molar mass of $B$ will be

If for a real number $y$,$[y]$ is the greatest integer less than or equal to $y$,then the value of the integral $\int_{\frac{\pi}{2}}^{\frac{3\pi}{2}} [2 \sin x] \,dx$ is

Assertion $(A)$: The aqueous solution of $CH_3COONa$ is alkaline in nature. Reason $(R)$: Acetate ion undergoes anionic hydrolysis. The correct answer is

Which of the following is a source of rubber?

At a given instant of time,the position vector of a particle moving in a circle with a velocity $\vec{v} = 3 \hat{i} - 4 \hat{j} + 5 \hat{k}$ is $\vec{r} = \hat{i} + 9 \hat{j} - 8 \hat{k}$. Its angular velocity $\vec{\omega}$ at that time is:

$P, Q$ and $R$ are long parallel straight wires in air,carrying currents as shown in the figure. The direction of the resultant force on wire $R$ is