Question

4720 kJ of energy are supplied to a material in order to raise its temperature by 65K. If the specific heat capacity of the material is 2730 J kg-1 K-1 then what is its mass?

Answer 1

Answer : The correct answer for mass of material = 26.6 Kg

Given : Q = 4720 KJ

Change in Temperature ( ΔT ) = 65 K

Specific heat capacity of material ( c) = 2730 $\frac{J}{Kg* K}$

The relation between Q , ΔT , c and m are related by following formula :

Q = m* c*ΔT ,

where Q = Heat or energy absorbed or released

m = mass , c = specific heat ,ΔT = change in Temperature

Plugging value in heat formula :

$4720 KJ = m * 2730 \frac{J}{Kg * K} * 65 K$

$4720 KJ = m * 177450 \frac{J}{Kg}$

[[Converting $177450 \frac{J}{Kg} to \frac{KJ}{Kg}$

$177450 \frac{J}{Kg} * \frac{1 KJ}{1000 J} = 177.450 \frac{KJ}{Kg}$ ]]

Dividing both side by $177.450 \frac{KJ}{Kg}$

$\frac{4720 KJ}{177.450 \frac{KJ}{Kg}} = m * \frac{177.450\frac{KJ}{Kg} }{177.450\frac{KJ}{Kg} }$

m = 26.6 Kg