Bell metal is an alloy of which of the following?

Two pendulums have time periods $T$ and $5T/4$. They start $SHM$ at the same time from the mean position. After how many oscillations of the smaller pendulum will they be again in the same phase?

In an $AC$ generator,a coil with $N$ turns,all of the same area $A$ and total resistance $R$,rotates with frequency $\omega$ in a magnetic field $B$. The maximum value of $emf$ generated in the coil is

The moment of inertia of a body about a given axis is $1.2 ~kg \cdot m^2$. Initially,the body is at rest. In order to produce a rotational kinetic energy of $1500 ~J$,an angular acceleration of $25 ~rad/s^2$ must be applied about the axis for a time duration of: (in $~s$)

The current $i$ in the circuit will be:

In printed scientific names, only the . . . . . . is capitalized.