When a primary amine reacts with chloroform in the presence of ethanolic $KOH$,the product formed is:

$A$ circular conducting loop of radius $R$ carries a current $I.$ Another straight infinite conductor carrying current $I$ passes through the diameter of this loop as shown in the figure. The magnitude of force exerted by the straight conductor on the loop is

Two different radioactive elements with half-lives $T_{1}$ and $T_{2}$ have undecayed atoms $N_{1}$ and $N_{2}$ respectively,present at a given instant. The ratio of their activities at this instant is

If $\alpha$ and $\beta$ are the roots of $x^2-2x+4=0$,then the value of $\alpha^6+\beta^6$ is

$A$ simple pendulum has a periodic time $T_1$ when it is on the surface of the Earth of radius $R$. Its periodic time is $T_2$ when it is taken to a height $R$ above the Earth's surface. The value of $\frac{T_2}{T_1}$ is

$A$ progressive wave of frequency $50 ~Hz$ is travelling with velocity $350 ~m/s$ through a medium. The change in phase at a given time interval of $0.01 ~s$ is