2020-22 Unit 6 LA C&D Project Implementation and Review Unknown
The effect of temperature change on viscosity
Practical logbook
Date Activity Outcome
24th Create a shopping list for items to needed brought Decided on the plant type and
January brand of nutrient to be used
25th I am going to order the fluid (oil) that I will need in I chose to use vegetable oil
January order to do my practical. as the fluid to find the effect it
CONTINGENCY: I researched the types of oil to has with temperature
see what would be the most effective for this
practical.
26th I researched methods that i could possibly use for I have researched and written
January the practical section of the project proposal and a possible method for my
have written a precise method which i have practical
adapted for my practical
27th I researched the different components of a risk I have knowledge of what to
January assessment and complete a risk assessment write in my risk assessment
based on the equipment i need to use for my and have completed a risk
experiment assessment for my
experiment
30th I ordered the marbles that i would use in the The reason I chose to use a
January practical and i also ordered plasticine just in case marble was because it's easy
the marbles are too heavy to find, it's not expensive and
is in the same shape.
6th Planned to undertake practical I completed the first practice
february CONTINGENCY: Make sure to have a backup practical experiment and
plan just in case this first one doesn't work collected the data
6th Create a table for the results of the practical and Practical experiment
february then start doing the practical, make sure to completed
consider safety before starting and while doing the
practical.
8th Work on more theory for the project plan I have completed some extra
february theory for the project plan
Part C.P4
Abstract
This experiment was carried out to test the effect of temperature change on viscosity of oil.
Hypothesis, as I increase the temperature of the material, the lower the viscosity meaning it
has a lower resistance flow while the terminal velocity increases. The results support this
hypothesis as the temperature increased and the time taken for the marble to reach the
bottom of the cylinder decreased. The hypothesis being investigated includes the use of a
water bath and a beaker full of ice/cold water that is done to have a variety of temperatures
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,2020-22 Unit 6 LA C&D Project Implementation and Review Unknown
making the investigation more accurate. Starting the temperature off by 10°C making their
way up to 70°C and adding the results onto a table. The results showed that the time taken
for the marble to reach the bottom of the cylinder decreases as the temperature of the
vegetable oil increases. The association of the variables were tested using the spearman’s
correlation coefficient. The estimated spearman's rank correlation coefficient was -1 which
means the null hypothesis is rejected and there is a close negative association between the
variables .
Introduction
Hypothesis
The hypothesis is that with higher the temperature of the fluid, the lower the viscosity
meaning it has a lower resistance flow while the terminal velocity increases.
Rationale for hypothesis
The hypothesis was as the temperature increases the viscosity decreases and the time
taken for the marble decreases. This hypothesis has been supported in previous
investigations that are similar to my investigation. For example an investigation was carried
out and how the temperature affects oil performance. Oil will become thinner or less viscous
in the heat. In the cold, it’ll become more viscous, or thicker (“How Temperature Affects Your
Oil | Minit-Tune”).This implies that you should use thinner oil in your car if you reside in a
really cold climate. This investigation is very similar to mine as the oil at high temperature
becomes more viscous and thinner then the oil at a low temperature becomes more viscous
and thicker. In conclusion it proves that my hypothesis is correct.
Viscosity is an essential part of liquids like oil that are used for lubrication, like lubricating oil
and grease.I chose this topic because there have been many experiments measuring
viscosity. (“Marble Race--in Liquid!”) This proves my hypothesis as the thicker the
substance is the longer it takes the marble to reach the bottom. The result of raising a
liquid's temperature is a decrease in cohesive forces and an increase in the rate of
molecular interchange (Fungilab, n.d.). The shear stress is reduced by the first effect while
increased by the second (Fungilab, n.d.). As a result, liquids exhibit a decrease in viscosity
with rising temperature. High temperatures cause the viscosity of gases to increase and the
viscosity of liquids to decrease (Fungilab, n.d.).A liquid's molecules are firmly bound together
by intermolecular forces when it is at room temperature (e.g.Van der Waal forces) (Fungilab,
n.d.). Since individual molecules are unable to move freely due to their close ties to their
neighbours, these attractive forces are to blame for the viscosity (Fungilab, n.d.).
The molecules become more mobile as a result of the rise in temperature, which also
causes the kinetic or thermal energy to rise (Fungilab, n.d.). Because the attractive binding
energy is lower, the viscosity is also lower (Fungilab, n.d.).An essential component of a
healthy diet is fat and oil. They are three fatty acid esters of glycerol from a structural
perspective (called either triacylglycerols or triglycerides). These fatty acids are what give
lipids their functionality (“Oils and Fats”, n.d.). Vegetable oils are made from plant sources
and make up the majority of the nutritious oil and fats produced annually around the world.
Oil viscosity is frequently determined and measured using either its absolute viscosity or its
kinematic viscosity (Singh and Heldman 2014, 1). Absolute viscosity, which is measured in
SI units of Pa, is an indicator of how difficult it is for oil to flow and shear as a result of
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, 2020-22 Unit 6 LA C&D Project Implementation and Review Unknown
internal friction. Kinematic viscosity, which is expressed in SI units of m2/s, refers to an oil's
resistance to flow and shear caused by gravity.By dividing the oil's absolute viscosity by the
corresponding density, one can determine the oil's kinematic viscosity (Singh and Heldman
2014, 1).
In order for a fluid to flow, layers of molecules must slide over one another. A streamline or
laminar flow occurs when motion only moves in the direction of the applied stress and is
characterised by slow, gentle flow. Because of the internal friction known as viscous drag
between the layers, this ordered motion does not absorb all of the energy present, but it is
still the flow that uses the least amount of energy (Curley, n.d.) (Lewis, n.d.). Using more
than one reference to prove a concept shows the reliability of it. When there is streamline
flow, the lines of flow are all parallel and are easily visible by adding a dye or by observing
the movement of the particles carried by the liquid. where a solid and liquid are in contact
(stationary if it is the bank of a river). The speeds of the layers gradually alter as you move
across the direction of flow through a liquid. As the velocity gradient rises and the viscous
drag forces increase, turbulent flow starts to appear (Curley, n.d.). Any obstruction or sharp
corner that disrupts the fluid's smooth flow can cause turbulence, which will then spread to
the nearby areas. The drag forces have a natural tendency to cause the fluid to rotate in
some places. Because turbulent flow absorbs much more energy than smooth flow, the
effective drag force also increases significantly (Curley, n.d.).
Method of investigation
Apparatus list
-5 test tubes
-Water bath
-Marble/small round object
-4 thermometers
-2 test tube stand
-Oil
-Ice cubes
-Digital balance
-cylinder 500ml
-Stop watch
-Measuring cylinder 50ML
-Paper towels
-Marker
-beaker
Ther
mom
eter
Wat
er
bath Sunfl
ower
Tes
t oil
Stop Be
tub
watc ak
esTest
h er
tube
Figure 1 shows the set up for my practical rack
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