Question

Calculate the quantity of heat required to raise the temperature of $5kg$ iron from $303K$ to $343K$. (Specific heat capacity of iron is $460Jk{g}^{-1}{K}^{-1}$)

• A. 90 kJ
• B. 92 kJ
• C. 460 kJ
• D. 90 kJ

Answer 1

The correct option is B 92 kJ

Given,
Mass of the iron, $m=5kg$
Specific heat capacity, $c=460Jk{g}^{-1}{K}^{-1}$
Change in temperature, $\theta =343-303=40K$
We know, heat required, $Q=\text{m}\times \text{c}\times \theta$
$=5\times 460\times (343-303)$
$=5\times 460\times 40$
$=92000J$ $=92kJ$