The magnetic field due to a straight conductor of uniform cross section of radius $a$ and carrying a steady current is represented by

$5.6 \ L$ of helium gas at $STP$ is adiabatically compressed to $0.7 \ L$. Taking the initial temperature to be $T_1$,the work done in the process is

Which one of the following statements is not correct?

The $H-$ zone in the skeletal muscle fibre is due to:

In the $CGS$ system,the magnitude of the force is $100 \text{ dynes}$. In another system where the fundamental physical quantities are kilogram,meter,and minute,the magnitude of the force is:

In the given circuit,find the equivalent resistance between points $a$ and the combination of $b$ and $c$ (where $b$ and $c$ are connected together).