Answer to Question #121562 in Electricity and Magnetism for Dheeraj

Question

The loss of energy due to hysteresis when 5kg of iron is subjected for 1hour to cylic magnetic changes of frequency 25cycles/sec, if the hysteresis loop represents a loss of 2500ergcm^(-3)cyclic^(-1) and density of iron is 7.8gmcm^(-3) is (in jouls)?

Answer 1

$n=$ Frequency =25 cycles/sec

$A=$ hysteresis loop represents a loss $= \frac {25 \times 10 ^{-7}}{10^{-6}}=25 \times 10^{-1}$

$V= \frac {m}{d}$ , $m$ =mass = 5 kg, $d =7.8 \times 10 ^3$

$tt = time =1Hr = 3600 sec$

Total energy loss  $E=nAVt=nA\frac {m}{d}t$

$E= 25 \times 2500 \times 10^{-1}\times \frac{5}{7.8\times 10^3}\times 3600$

$E=14.42 \times 10^3 J$