A metal rod is subjected to cycles of magnetisation at the rate of 42 Hz. Density of the metal is 6 × 103 kg m -3 and its specific heat capacity is 0.1 × 103 cal kg 1 ° C 1. If the area of its B-H loop corresponds to energy density of 10-2 Jm -3, then the rise in its temperature in one minute is

Question

A metal rod is subjected to cycles of magnetisation at the rate of 42 Hz. Density of the metal is 6 × 103 kg m -3 and its specific heat capacity is 0.1 × 103 cal kg 1 ° C 1. If the area of its B-H loop corresponds to energy density of 10-2 Jm -3, then the rise in its temperature in one minute is (A) 5° C (B) 10° C (C) 15° C (D) 20° C

Tardigrade Admin · Accepted Answer

Energy of area of B-H loop, Δ Q=m s(Δ θ) ⇒ 10-2 × 42 × 60=6 × 103 × 0.1 × 10-3 × 4.2 × Δ θ ⇒ Δ θ=(10-2 × 42 × 60/6 × 103 × 0.1 × 10-3 × 4.2) ⇒ Δ θ=10° C

$5^{\circ} C$

$1 0^{\circ} C$

$1 5^{\circ} C$

$2 0^{\circ} C$

Q. A metal rod is subjected to cycles of magnetisation at the rate of 42Hz. Density of the metal is 6×103kgm−3 and its specific heat capacity is 0.1×103 cal kg1∘C1. If the area of its B−H loop corresponds to energy density of 10−2Jm−3, then the rise in its temperature in one minute is

5∘C

10∘C

15∘C

20∘C

Energy of area of B−H loop, ΔQ=ms(Δθ) ⇒10−2×42×60=6×103×0.1×10−3×4.2×Δθ ⇒Δθ=6×103×0.1×10−3×4.210−2×42×60​ ⇒Δθ=10∘C

$5^{\circ} C$

$1 0^{\circ} C$

$1 5^{\circ} C$

$2 0^{\circ} C$