Aim: To investigate the rate of cooling of water in two different containers.Apparatus:==> A testube==> A beaker==> 2 digital thermometers (? 0.05?C)==> A testube holder (wooden)==> Measuring cylinder==> Warm water ( around 45 – 50?C)==> 2 stopwatchesProcedure:1. Pour 20ml of water into a measuring cylinder and then pour it into a beaker.
2. Pour another 20ml into a testube.3. Place thermometers in both the containers and record the starting temperatures.4. Start the stopwatches simultaneously.
5. Just when thirty seconds get over, record the temperatures that the thermometers reflect instantaneously.6. Continue this recording every thirty seconds.7. Stop after 10 minutes.
8. At the end observe the difference in the total decrease in temperature.Modifications in procedure:==> The readings were simultaneously recorded every 30 seconds for direct comparison.==> The readings were taken for ten minutes.
==> Both the containers were exposed to the same material, wood, which had the same insulating effect on the containers.==> Two sets of readings for each container were taken.Experimental setup:Maintaining Fair test:==> The volume of water was kept constant.==> The same insulation was exposed to both the containers.==> The atmospheric conditions were kept constant.
Safe Test:==> Be careful while collecting hot water from the kettle.==> Be careful not to knock over any beaker or container containing hot water.Observation:Raw Data:Table 1: Table showing the gradual decrease in temperature of water held in two containers over ten minutes.Time(secs)Beaker (? 0.05?C)Testube (? 0.05?C)Reading 1Reading 2Reading 1Reading 2044.245.
635.439.460034.718.104.22.168As the purpose of this experiment is to compare the rate of cooling between water in two different containers there would be no need to club the readings as averages but there would be a need to club the overall change in temperature as an average to figure out which has a higher rate of cooling.Processed Data:Table 2: Table showing the total and average change in temperature over 10 minutes for the respective containersBeakerTestubeReading 1Reading 2Reading 1Reading 29.522.214.171.124Average = 10.6Average = 8.5Method used:The final temperature after ten minutes is subtracted from the initial temperature.For eg: 9.5 = 44.2 – 34.7Conclusion:After an analysis of the results, it can be concluded that the more the surface area of water exposed to atmosphere, the higher the rate of cooling. Thus, the bigger the container, the faster the rate of cooling.