(1) Latent heat of steam is 540 cal/gm. Express this in SI units.
(2) A liquid has a mass of 200 gm and a specific heat capacity of $0.8 c a l / g m / C^{o}$ . Find water equivalent of the liquid.

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Solution

(a) Latent heat of steam is $540 c a l / g m$

$1 c a l = 4.184 J$

$s o,$

$500 c a l / g m = 500 \times 4.184 \times 1000$

$= 20, 92, 000 J / K g$

(b) Water equivalent is defined as the product of mass and specific heat

Water equivalent

$= 200 \times 0.8$

$= 160 c a l / C^{0}$

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