If $W_1, W_2$ and $W_3$ represent the work done in moving a particle from $A$ to $B$ along three different paths 1,2 and 3 (as shown in fig) in the gravitational field of the point mass ' $m$ '. Find the correct relation between ' $W_1$ ', ' $W_2$ ' and ' $W_3$ '

Assuming that the junction diode is ideal, the current in the arrangement shown in figure is

The equation of simple harmonic progressive wave is given by $Y=a \sin 2 \pi(b t-c x)$. The maximum particle velocity will be twice the wave velocity if

In a fundamental mode,the time required for the sound wave to reach upto the closed end of a pipe filled with air is ' $t$ ' second. The frequency of vibration of air column is