# A2 Viscosity investigation

Investigation to determine the viscosity of golden syrup and the effect temperature has on this.

I will determine the viscosity of syrup at the following temperatures (10°C, 20°C and 30°C). I will be plotting my results on separate graphs to determine the viscosity and then plot them on the same graph to help determine the effect of temperature.

Apparatus:

Golden syrup

Measuring cylinder

5 ball bearings of varying sizes

Weighing scales

Stop clock

Micrometer

Nitre rule

Magnet (to get ball bearings out of syrup)

Thermometer

Water bath

For the density of steel I will use the accepted value of 7850kgm-3. To work out the density of golden syrup I will measure the weight of 50cm3 and use the formula ρ= where m is mass and v is volume. I will do this for each temperature I temperature will affect the density.

Method:

1. Using the micrometer measure the diameter of the ball bearing.
2. Weigh the ball bearing using the weighing scales and record the results in a table.
3. Measure 6cm on the measuring cylinder and draw two lines draw the line all the way around the cylinder as this will make it easier to ensure you are at eye level. (ensure the first line is at least 3cm from the top of where the syrup is filled to as it needs time to reach terminal velocity)
4. Place the ball bearing into the syrup then get to eye level of the first line to ensure maximum accuracy and then start the timer when the bottom of the ball bearing touches the line previously drawn.
5. Kneel until you are at eye level of the second line and wait until the bottom of the ball bearing touches the line and stop the timer.
6. Record the time in a table so the results can later be used to find the velocity.
7. Repeat steps 1-8 for the other size ball bearings which are.
8. Repeat each measurement 3 times and fond an average.
9. Once all the above steps are complete for syrup at room temp then do the above steps for the syrup at 30 and 40°C use the water bath to heat the syrup to these temperatures.

The sensitivity of the measuring apparatus must be considered and the correct procedures to obtain the most accurate readings must be discussed. The micrometer measures with a sensitivity of +or- 0.1mm. to use this accurately ensure that the ball bearing lays in the centre of the micrometer to ensure it doesn’t move so you can obtain an accurate reading also ensure that the micrometer is correctly set to 0 before you start your measurements. The metre rule can be used to measure with a sensitivity of +or- 0.5mm to use this accurately ensure that the metre rule is parallel to the object you need to measure. The weighing scales measures to an accuracy of 0.005Kg again ensure the scales are correctly set to 0 before you begin taking your readings. The stop clocks sensitivity is +or-0.05s but as it is not electronically controlled and it is based on human judgement and reaction time the actual error for this part will be greater than that stated.

To reduce percentage errors comparatively greater amounts of syrup have been used as the uncertainties in the equipment will make up a less percentage error of a larger volume. I have disregarded calculating the value of steel as the uncertainties would play a major role instead I have just taken the accepted value (stated earlier). As previously stated the timing will not begin until the ball has travelled a few cm and is at terminal velocity this is because the equations will only work at terminal velocity and if this is not the case the results will not be very ...