Question

The magnetic susceptibility of a paramagnetic material at -80^0C is 0.0085, then what is its value at -180^0C?

(a) 0.015

(b) 0.016

(c) 0.017

(d) 0.018

I got this question in homework.

The above asked question is from Magnetic Properties of Materials in division Magnetism and Matter of Physics – Class 12

Answer 1

The correct choice is (c) 0.017

To explain: Given: χm1 = 0.0085; T1 = -80^0 C = -80 + 273 = 193 K; T2 = -180^0 C = -180 + 273 = 93 K

χm ∝ \(\frac {1}{T}\)

\(\frac {\chi_{m2}}{\chi_{m1}} \, = \, \frac {T_1}{T_2}\)

\(\frac {\chi_{m2}}{0.0085} \, = \, \frac {193}{93}\)

χm2 = \(\frac {193 \, \times \, 0.0085}{93}\)

χm2 = 0.017