A particle is performing S.H.M. starting from extreme position. Graphical representation shows that between displacement and acceleration, there is a phase difference of

The plot of magnetic flux ' $\phi$ ' linked with the coil versus current ' I ' is as shown in figure for two inductors $\mathrm{L}_1$ and $\mathrm{L}_2$. The self inductance of

A musical instrument ' P ' produce sound waves of frequency ' $n$ ' and amplitude ' $A$ '. Another musical instrument ' $Q$ ' produces sound waves of frequency ' $\frac{\mathrm{n}}{4}$ ' The waves produced by ' P ' and ' $Q$ ' have equal energies. If the amplitude of waves produced by ' P ' is ' $\mathrm{A}_{\mathrm{p}}$ ', the amplitude of waves produced by ' $Q$ ' will be