Correct Answer - Option 3 : Critical current density
Explanation:
Critical current density is the structure sensitive property of a super conductor.
The Silsbee effect states that, if the current exceeds a critical level, the superconducting state will be destroyed.
Critical current is mathematically defined as:
IC = 2πr Hc
r = radius of superconductor wire
Hc = critical magnetic field strength
Critical current density will be the ratio of the critical current to the area, i.e.
\({J_c} = \frac{{{I_c}}}{A}\)
\({J_c} = \frac{{2\pi r\;{H_c}}}{A}\)
\({J_c} = \frac{{2\pi r\;\;{H_0}\left[ {1 - {{\left( {\frac{T}{{{T_c}}}} \right)}^2}} \right]}}{A}\)
