Exponential Decay in Reality

Exponential Decay in Reality

[IMAGE]

Instructions to operate

* Kettle to the boil

* Pour 500ml of water in cup (plastic)

* Place thermometer in water

* Take temperature every minute for the 1st 30 mins and then every

5mins for the next 30 min and then every 10 mins until it is back

to room temperature.

* Experiment conducted 3 x (results averaged)

* Used the exact same equipment for each experiment (water type,

container, thermometer, kettle)

[IMAGE]

My apparatus is designed to simulate the process of exponential decay.

The model was measuring the temperature drop from boiling water. It

was considered that the temperature would only ever drop to room

temperature, therefore the temperature difference between the water

temp and the room temp was measured to get a final reading of zero,

which outlines NewtonÂ’s cooling law.

From experimental observations it is known that (up to a

``satisfactory'' approximation) the surface temperature of an object

changes at a rate proportional to its relative temperature. That is,

the difference between its temperature and the temperature of the

surrounding environment. This is what is known as Newton's law of

cooling.

In the process of undertaking this experiment many assumptions were

made.

* Taking into account the water was poured from the kettle, a

reading of the temperature of the water was not taken, until it

was in the cup, therefore I assumed that the initial temperature

was of 100ËšC

* The experiment was conducted 3 times to obtain the best results in

doing so; I assumed that the water ingredients remained the same

for each experiment.

* It was also considered that the container used did not make a