Electrical resistance of certain materials, known as superconductors, changes abruptly from a non-zero value to zero as their temperature is lowered below a critical temperature `T_(C)(0)`. An interesting property of superconductors is that their critical temperature becomes smaller than `T_(C)(0)` if they are placed in a magnetic field i.e., the critical temperature `T_(C)(B)` is a function of the magnetic field strength B. The dependence of on B is shown in the figure.

A superconductor has `T_(C)(0)=100K`. When a magnetic field of 7.5 T is applied its `T_(C)` decreases to 75 K. For this material one can definitely say that when (Note T-Tesla)

Options

A.
B.
C.
D.

Answer

A

Explanation

If `B_(2)gtB_(1)`, critical temperature, (at which resistance of semiconductors abruptly becomes zero) in case 2 will be less than compared to case 1 .
`:.` The correct option is (A)