Answer: 110 cal
It is given that he specific heat of Iron is [tex] 0.11 cal/g^o C[/tex].
Mass of iron fork 20 g
Heat energy is needed to raise the temperature of this from [tex] 25^o C to 75^o C [/tex]
we can use the following formula to calculate heat energy:
[tex] Q=mC \Delta T [/tex]
where Q is the heat required to raise the temperature by [tex]\Delta T[/tex] of a mass m having specific heat C.
Insert the values:
[tex] Q=20 g \times 0.11 cal/g^oC (75^o C -25^o C)\\\Rightarrow Q=(2.2\times50)cal=110 cal[/tex]
Thus, heat required to raise the temperature of iron fork is 110 cal.