– N5 Physics Assignment
To investigate if the pressure of a gas which has a constant
mass varies when the volume is changed.
The particles in different gases have a lot of free space to
move around in which means they tend to collide with each other and bounce off
of the container walls. Collisions are likely to occur more often when the
volume is decreased. The particles will have more energy if the temperature is
increased which means that there will be more collisions per second which will
mean that particles will collide with a much larger force. Pressure is the
force per the unit of area and can be determined by the equation:
P= Pressure in (Pa)
F= Force in (N)
A= Area in (m2 )
The Kelvin scale can change 0 Celsius into -273o K. To
convert Celsius to Kelvin you simply just do the calculation of (degrees Celsius)
– 273, this will give you your answer in Kelvin. This lets us know the volume of
a selected gas as you can work backwards for example if you know the gas is 243o
K you will know the temperature is 30o C.
The air was trapped in a cylindrical container with oil. The
container was connected to a pressure gauge and a pump. The pressure gauge was
there to measure the pressure and the pump decreased the amount of air which
was in the cylindrical container.
The following values are the results of the experiment
pressure against 1/Volume:
With the results above we plotted a graph with a line of best
The second source I have compares with my own graph as they
are both a straight line which goes through the origin. This shows that if
volume increases, pressure decreases. See
next page for second source.
The aim of the experiment I did was to investigate if the
pressure of a gas which has a constant mass varies when the volume is changed.
The experiment results show that there is definitely some relationship between
the change in pressure and volume.
To make my experiment more accurate I did the experiment
three times and with these results I calculated the average. Having three sets
of results meant that there was more of a chance for an accurate experiment due
to having more values to work with.