An inductor coil carries a steady-state current of $2.0 \, A$ when connected across an ideal battery of $emf \ 4.0 \, V$. If its inductance is $1.0 \, H$,find the time constant of the circuit in $sec$.

$A$ closed pipe is suddenly opened and changed to an open pipe of the same length. The fundamental frequency of the resulting open pipe is less than that of the $3^{rd}$ harmonic of the earlier closed pipe by $55 ~Hz$. Then,the value of the fundamental frequency of the closed pipe is: (in $~Hz$)

Which of the following pairs of monosaccharides form sucrose?

In an elastic collision of two particles,which of the following is conserved?

Which one of the following equations is correct for the reaction $N_{2(g)} + 3H_{2(g)} \longrightarrow 2NH_{3(g)}$?

Which one is an incorrect statement?