Question

why is at 273kmore effective in calling than water at the same temperature.

Answer 1

because it has been recomneded to use kevlvin over degree centigrade or farheit

Answer 2

So, at same temperature of 273 K, large amount of heat will be removed by ice from the surroundings than in case of water. Hence, ice at 273 K is more effective in cooling than water at the same temperature.
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