When the temperature of an iron sphere of mass $1kg$ falls from ${30}^{o}C$ to ${25}^{o}C$ , then $550cal$ of heat is released. The heat capacity of the iron sphere will be ( in $ca{l}^o{C}^{-1}$ )

The correct option is D $110$
Since the same amount of heat would be required to raise the temperature from ${25}^{\circ }C$ to ${30}^{\circ }$ as released when temperature falls in same fashion(conservation of energy),

$H=HeatCapacity\times \Delta T$

$⟹HeatCapacity=\frac{550}{5}=110cal{/}^{\circ }C$