Day 01:
Room temperature - 29ºc
Initial water temperature - 23ºc

10.30 am          -           23ºc
11.00 am          -           21ºc
11.45 am          -           20ºc
12.45 pm          -           19ºc
01.45 pm          -           19ºc
02.45 pm          -           19ºc

Result:
Temperature difference of 4ºc in 2 hours and 15 minutes.

Day 02:
Water taken in this day was hot water.
Room temperature - 26ºc
Initial water temperature - 37ºc

09.45 am          -           37ºc
09.55 am          -           35ºc
10.25 am          -           30ºc
10.55 am          -           28ºc
11.25 am          -           25ºc
12.00 noon       -           24ºc
12.30 pm          -           23ºc
01.15 pm          -           23ºc
01.45 pm          -           23ºc
02.45 pm          -           22ºc

Result:
Temperature  differences  initially  were high and later it slows down.

Day 03:
The experiment was conducted in the night time.
Room temperature - 23ºc
Initial water temperature - 23ºc

06.15 pm          -           23ºc
07.15 pm          -           23ºc
09.45 pm          -           22ºc
11.00 pm          -           22ºc
12.15 am          -           22ºc
09.00 am          -           21ºc
10.00 pm          -           21ºc

Result:
In  the  night  the outside  temperature  is low, so the water cooling happens very slowly. The water cooling will happen faster only when the outside temperature is high.