The surface temperature of a swimming pool on a warm day is 25oC and the temperature at the bottom is 15oC. If the swimming pool has a surface area of 620 m2 and a depth of 1.5m. Find the rate at which energy is transferred by conduction from the surface to the bottom of the swimming pool.

[Thermal conductivity of water (k) = 0.6071 Wm-1K-1]

A. 2.5kw

B. 250kw

C. 300kw

D. 3.0kw

Correct Option: Answer is A

The rate of energy transfer by conduction (Q) can be calculated using the formula:

Q=k⋅A⋅ΔT/d

where:

• k is the thermal conductivity of the material (given as 0.6071 Wm⁻¹K⁻¹ for water),

• A is the cross-sectional area through which heat is conducted (given as 620 m² for the surface area of the pool),

• ΔT is the temperature difference (given as 25°C – 15°C = 10°C),

• d is the thickness of the material through which heat is conducted (given as the depth of the pool, 1.5m).

Substitute these values into the formula:

Q =0.6071 Wm−1K−1⋅620 m2⋅10 K/1.5 m