Question

How much heat is absorbed by a $2000\text{ }kg$ granite boulder as energy from sun causes its temperature to change from $10{}^\circ C\text{ }to\text{ }29{}^\circ C$ ?

Answer 1

We know that the specific heat capacity of substance which is defined as heat energy required to raise temperature or as we can have unit mass of substance by $1{}^\circ C$ The term was initially define such that specific heat capacity of a water would be given as L this resulted in unit of energy called as calories.

Complete step-by-step answer: The term specific heat capacity is define to determine the amount of a heat required to raise temperature of unit mass of water by $1{}^\circ C$ Since water is most commonly use liquid in a calorimeter thus a new unit of energy is defined it's called calories.
A calorie is defined as amount of a heat required to raise temperature of a $1$ gram of the water by
$1{}^\circ C$ According to specific heat capacity of water is $1\text{ }\dfrac{cal}{g\cdot {}^\circ C}$
The dimensions units which we use in value and units given in questions are different.
Heat absorbed is given by
$H\text{ }=\text{ }m\cdot c\cdot \partial \left( \theta \right)\text{ }\ldots \ldots \ldots \ldots \ldots \ldots ..\left( 1 \right)$
here $m\text{ }=$ mass along with $c\text{ }=$ specific heat capacity
Assuming $c\text{ }=\text{ }790\text{ }\dfrac{J}{kg}/K$ for granite
Here, ∂(theta) is the change in temperature
$\partial \left( \theta \right)\text{ }=\text{ }29\text{ }-\text{ }10\text{ }=\text{ }19K$
Therefore now re-substituting values in equation of heat absorbed that is $\left( 1 \right),$
$H\text{ }=\text{ }2000\text{ }\times \text{ }790\text{ }\times \text{ }19$
$H\text{ }=\text{ }3002000\text{ }J$
$H\text{ }=\text{ }3.002\text{ }MJ$
Therefore, $3.002\text{ }MJ$ amount of heat is absorbed by a $2000\text{ }kg$ granite boulder as a energy from sun causes its temperature to change from $10{}^\circ C\text{ }to\text{ }29{}^\circ C$

Note: Note that the term calories is defined specifically keeping property of a water, therefore most of the time value corresponding to water in a calorie is unity. The joule on the other hand is derived from other metric units as well as it has to be equated with calories to find equivalent value.