To solve this problem it is necessary to apply the concepts related to heat transfer and power depending on energy and time.
By definition we know that the heat loss of water is given by
[tex]Q = mc_w*\Delta T+m*L_f[/tex]
Where,
m = mass
[tex]c_w =[/tex] Specific Heat of Water
T = Temperature
[tex]L_f =[/tex]Latent heat of fusion [tex] \rightarrow[/tex] Heat of fusion for water at 0°C is [tex]3.35*10^5J/Kg[/tex]
Our values are given as,
m=53 kg
[tex]C=4180 J/kg\°C[/tex]
[tex]\Delta T=10-(-1)=11[/tex]
Replacing we have,
[tex]Q=53*4180*6+53*3.35*10^5[/tex]
[tex]Q = 19084240J[/tex]
Power can be defined as
[tex]P = \frac{Q}{t}[/tex]
Re-arrange to find t,
[tex]t = \frac{Q}{P}[/tex]
[tex]t = \frac{19084240}{1200}[/tex]
[tex]t = 15903.53s \approx 265 min \aprox 4.41h[/tex]
Therefore the time interval is 4.41h