A solid metal weighing $150$ g melts at its melting point of $800$ $^{o} C$ by providing heat at the rate of $100$ W. The time taken for it to completely melt at the same temperature is $4$ min. What is the specific latent heat of fusion of the metal?

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Solution

Mass of ice to melt $m = 150 g = 0.15 k g$
Rate of heat supplied $P = 100 W$
Time taken $t = 4 m i n = 4 \times 60 s = 240 s$
Total heat supplied $H = P t = 100 \times 240 = 2.4 \times 10^{4} J$
Specific latent heat of fusion of metal $L = \frac{H}{m}$
$⟹ L = \frac{2.4 \times 10^{4}}{0.15} = 1.6 \times 10^{5} J / k g$

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A solid metal weighing 150g melts at its melting point of 800 oC by providing heat at the rate of 100W. The time taken for it to completely melt at the same temperature is 4 min. What is the specific latent heat of fusion of the metal?

Mass of ice to melt m=150 g=0.15 kgRate of heat supplied P=100 WTime taken t=4 min=4×60 s=240 sTotal heat supplied H=Pt=100×240=2.4×104 JSpecific latent heat of fusion of metal L=Hm⟹ L=2.4×1040.15=1.6×105 J/kg

A solid metal weighing $150$ g melts at its melting point of $800$ $^{o} C$ by providing heat at the rate of $100$ W. The time taken for it to completely melt at the same temperature is $4$ min. What is the specific latent heat of fusion of the metal?