A piece of iron of mass 2.0 kg has a heat capacity of 966 J K^-1 . Find (i) heat energy needed to warm it by 15° C, and (ii) it's specific heat capacity in S.I unit.

(i) Given,

mass (m) = 2.0 kg

heat capacity (C') = 966 J K^-1

rise in temperature (△t) = 15°C

Heat energy needed (Q) = ?

From relation,

Q = C' × △t

Substituting the values in the formula above we get,

Q = 966 x 15 = 14,490 J

Hence, heat energy needed to warm it by 15°C = 14,490 J

(ii) specific heat capacity (c) = ?

We know that,

$c = \dfrac{C'}{m} \\[0.5em]$

Substituting the values in the formula above we get,

$c = \dfrac{966}{2} = 483 \text{ J kg}^{-1} \text{K}^{-1}$

Hence, Specific heat capacity = 483 J kg^-1 K^-1