Question

How much heat energy in Kilocalories necessary to raise the temperature of 5 Kg of water from 20 degree Celsius to 50 degree Celsius.​

Answer 1

Given :

• T1 = 20°C

• T2 = 50°C

• Mass of water = 5 kg

To find :

Heat energy required to raise the temperature.

Solution :

We know the formula for Heat energy i.e,

$\boxed{\bf{Q = m C_{p} \Delta T}}$

Where :

• Q = Heat energy

• C = Specific heat capacity

• ∆ T = Change Temperature

Now using the formula for Heat energy and substituting the values in it, we get :

$:\implies \bf{Q = m C_{p} \Delta T}$

We know that ∆T is the change in temperature , hence it can written as the difference in the Final Temperature and Intial Temperature.

Here ,

• Intial Temperature = 20°C

• Final Temperature = 50°C

Now by substituting it in the equation , we get :

$:\implies \bf{Q = m C_{p} (T_{f} - T_{I})}$

We know that , Specific heat capacity (C) for water is 4.2 J , by substituting it in the equation we get :

$:\implies \bf{Q = 5 \times 4.2 \times (50^{\circ}C - 20^{\circ}C)}$

$:\implies \bf{Q = 5 \times 4.2 \times (50^{\circ}C - 20^{\circ}C)}$

$:\implies \bf{Q = 5 \times 4.2 \times 30^{\circ}C}$

$:\implies \bf{Q = 21 \times 30^{\circ}C}$

$:\implies \bf{Q = 630\:J}$

$\boxed{\therefore \bf{Q = 630\:J}}$

Hence the heat energy required to raise the temperature is 630 J.