Sunday, 8 July 2012

FUN with PEKA FORM 4 ... relationship between pressure and density ..

  assalamualaikum wbt ...

It is an exciting moment when my students keep trying and trying to accomplish their mission to proof the hypothesis in the experiment.

On 4th July 2012, the experiment was handling as to investigate the relationship between the pressure and density of liquid besides exposing them with new apparatus called manometer and thistle funnel.

As the density of a liquid increase then the pressure of a liquid also increase.

The students have been provided 3 solutions which is alcohol solution, salt solution and distilled water. To begin with, which one of those has higher density ???

 They already know that the highest density is salt solution. However, between alcohol and distilled water which one has higher density? Why? Lots of answer came out  ... and most of them keep saying alcohol is denser.

Here’s the way to prove ..

Density is defined as mass per unit volume

So, i let them to measure the mass of both solutions and calculate the density...

so, which one...??
Water is denser than alcohol because the space between water molecules is less than the space between alcohol molecules. Hence, there is more matter per unit volume of water than per unit volume of alcohol. Since a unit volume of water contains more matter than an identical volume of alcohol, its density is greater.

At the beginning of the experiment, they quite frustrated as the yellow liquid in the manometer didn’t rise up...they setup again the apparatus and manage the rubber tube that connected the thistle funnel and the manometer in the other way... yesss!!!now it rise...

They were so happy, but then they got headache again as I keep saying "your result was wrong" ... READ THE METHOD AGAIN! STUDY CAREFULLY THE APPARATUS ARRAGEMENT I GAVE YOU!

 ...arghhh...they start to stress ... but they keep trying and trying ... we took the wrong ‘h’ ... oh no ... hahaha..

they began the reading and enjoy again ....