DISCUSSION Based on Hoeppler Method, to determine the dynamic viscosity using HAAKE Falling-ball viscometer is in accordance with the equation. According to the equation, the viscosity of fluids can be determined from the viscometer ball constant, K, density of the ball and viscous fluid with the value of falling time of the ball that has been recorded. The value for the viscometer constant, K has been given. All the information and data that has been taken is recorded in the data sheet. All information that has been filled in the data sheet leads to the value of the viscosity. Based on the data, it is clearly observed that the viscosity of glycerine is higher than water which is determined by the calculation of viscosity by using the equation and also the time taken for each ball to reach the bottom mark. The viscosity value of glycerine from the experiment is too low than the theoretical value that quoted in literature which is 9420 mPa.s. The viscosity of glycerine is greater than water. This is because of the hydrogen bonds between the positively charged hydrogen atoms and the negatively charged oxygen atoms. Glycerine, on the other hand, contains three hydroxyl groups, which leads to a higher number of hydrogen bonds and therefore stronger bonds between molecules and higher viscosity. On top of that, according to the Newton’s law of viscosity, both water and glycerine are considered as the Newtonian fluid.
DISCUSSIONBased on Hoeppler Method, to determine the dynamic
viscosity using HAAKE Falling-ball viscometer is in accordance with
the equation. According to the equation, the viscosity of fluids
can be determined from the viscometer ball constant, K, density of
the ball and viscous fluid with the value of falling time of the
ball that has been recorded. The value for the viscometer constant,
Khas been given. All the information and data that has been taken
is recorded in the data sheet. All information that has been filled
in the data sheet leads to the value of the viscosity.Based on the
data, it is clearly observed that the viscosity of glycerine is
higher than water which is determined by the calculation of
viscosity by using the equation and also the time taken for each
ball to reach the bottom mark. The viscosity value of glycerine
from the experiment is too low than the theoretical value that
quoted in literature which is 9420 mPa.s.The viscosity of glycerine
is greater than water. This is because of the hydrogen bonds
between the positively charged hydrogen atoms and the negatively
charged oxygen atoms.Glycerine, on the other hand, contains three
hydroxyl groups, which leads to a higher number of hydrogen bonds
and therefore stronger bonds between molecules and higher
viscosity. On top of that, according to the Newtons law of
viscosity, both water and glycerine are considered as the Newtonian
fluid. In order to obtain how accurate this experiment was carried
out, the percentage difference must be calculated. The calculation
revealed this experiment has a very high percentage difference.
This means that there might be possible errors that could have
taken place.
There are many solutions to cope with the error. Before using
the vernier calipers, thejaws must beclosed withnothing between
them to checkthe presence of zero error. If there is zero error,
the vernier calipers need to compensate accordingly. In order to
compensate for the error, all readings taken with this vernier
calipers should be adjusted by deducting or adding the value of
zero error with the actual reading. Error in operating the
viscometer equipment can be reduced by taking several readings of
the same quantity and same angle of turns thus subsequently
obtaining the average value. To make sure the uniformity of the
temperature of the viscometer, the tube needs to be turn upside
down at least once for the spherical ball run through up and
down.
