Question

A swimming pool, 10.0 m by 4.0 m is filled to a depth of 3.0 m with water at a temperature of 20.2oC. How much energy is required to raise the temperature of the water to 30.0 oC?

Answer 1

Answer:

It is required 1482 Megajoules of energy.

Explanation:

The energy Q required to raise the temperature T1 to a temperature T2 of mass m of water is:

$Q=cm\(T_2-T_1)$ (1)

with c the specific heat of water that is$c=4200\frac{J}{kg oC}$.

We don't have explicit the mass of water containded in the swimming pool, but we can use the relation:

$m=V\rho$

with ρ the density of water that is $1000\frac{kg}{m^3}$, V the volume of the swimming pool and m the mass, so m is:

$m=(3.0)(4.0)(3.0)1000=36000kg$

Using c and m on (1):

$Q=cm(T_2-T_1)=(4200)(36000)(30.0-20.2)=1482 MJ$