• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Calculating the viscosity of Glycerol.

Extracts from this document...



Calculating the viscosity of Glycerol


Viscosity is a measure of the resistance against the flow of a substance (fluid). The higher the viscosity of a fluid, the less easily it can flow. The viscosity of a fluid can be calculated by using Stroke’s Law, which relates the viscosity of a fluid to the viscous drag (opposing force) and velocity at which it is travelling. One method of calculating the viscous drag (also the method I will be using) is by subtracting the upthrust exerted by the fluid on an object (ball) from the weight of the object as it is dropped through the fluid, assuming that the object has reached it’s terminal velocity and therefore has equal forces acting on it.


To observe and record the terminal velocities of different sized balls falling through Glycerol, and hence calculate the viscosity of Glycerol.


The only variables that will be changed for us to gain a range of results will be the size of the balls.

...read more.



  • Cylindrical tubing (blocked off at bottom)
  • Rubber bands/tape for marking start and stop distances
  • Metre ruler, stopwatches and micrometer
  • Glycerol and set of different sized balls (densities assumed to be the same and constant through the balls and fluid)
  • Measuring tube/flask and balance to obtain a volume and mass for the calculation of densities.


        For this investigation, I am not expecting to obtain perfect results as there are a number of errors that are likely to occur due to the limitations of our apparatus and judgement. For one, the times we obtain may not be absolutely correspond, as we our using our own eyesight and stopwatches to gain this measurement, and is therefore limited to the speed of our reaction. Also, it cannot be guaranteed that the balls we use have gained maximum velocity, although the results may show that there is very little variation in the times (especially with larger balls, as their mass and therefore weight will cause them to move faster). I am also predicting that the graph we plot of radius2

...read more.



        There are many improvements that can be made to give more accurate results for this experiment, although most of the changes that could be made do not include much that is possible with the apparatus that was provided. However, if more accurate and precise apparatus were to be used to take measurements, it would not dramatically affect the results over the length of tubing that is suitable for the conditions we had to work under. The main reason as I suggested before, for our inconsistent results was due to the balls not having reached their terminal velocity. The only method of allowing these balls to reach their terminal velocity would be to let them fall for a larger distance before recording the time’s. This is one improvement that could significantly better the experiment, any others being new methods of measuring the densities and velocities more accurately, maybe by using an electronic speedometer.

...read more.

This student written piece of work is one of many that can be found in our GCSE Forces and Motion section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Forces and Motion essays

  1. An Investigation into the terminal velocity of steel ball bearings in Glycerol.

    the ball bearings with the magnet, I also removed a small amount of glycerol. Over several retrievals, a considerable amount of glycerol may have been removed. If the volume changes enough, then the final results will be too varied, as density of fluid is dependant on volume.

  2. The effect of the temperature on the viscosity of the syrup.

    Hence it will also affect the viscosity of the syrup. Temperature of the syrup - When the temperature is altered, the speed at which the molecule travels also changes. In effect the viscosity of the syrup also changes. Preliminary work To have an idea of the effect of different temperatures on syrup I will carry out preliminary work.

  1. Bouncing balls.

    h(mean) h(max) h(min) 2 1.1 1.1 1.11 1.09 1.12 1.104 1.12 1.09 1.8 1 1.01 1.01 1.02 1.03 1.014 1.03 1 1.6 0.91 0.91 0.9 0.9 0.89 0.902 0.91 0.89 1.4 0.79 0.77 0.78 0.78 0.78 0.78 0.79 0.77 1.2 0.68 0.7 0.68 0.67 0.69 0.684 0.7 0.67 1

  2. Viscosity of Fluids

    Firstly weigh the ball bearing and measuring cylinder; accurately measure the diameter of the ball bearing and note down the measurements.


    This affects the measurements taken for the steel balls. * Not dropping the steel balls through the centre of the tube could cause them to have contact with the walls and generate friction, which affects the results. * Inconsistency which gives rise to differences in temperature could change the viscosity.

  2. Practical Investigation Into Viscosity

    69.3 cP Air @ 18�C 0.018 2 cP Olive oil @ 20�C 84.0 cP Argon @ 20�C 0.022 17 cP Light machine oil @ 20�C 102 cP Air @ 229�C 0.026 38 cP Heavy machine oil @ 20�C 233 cP Neon @ 20�C 0.031 11 cP Caster oil @ 20�C

  1. Investigation into the effect of temperature on viscosity

    could be measured and the weight/force calculated it makes more sense to keep both the forces (upthrust and ball weight) in the same format to allow them to be easily combined. Ball weight: Mass= 4/3 Pi r3 ?steel Weight of the ball= (4/3 Pi r3 ?steel)

  2. This investigation is associated with the bounce of a squash ball. I will be ...

    Ball Behaviour Why does a squash ball bounce higher when it's warm? In order for a solid material to be deformed, work has to be done on it. For that work to be done, energy must be expended (in the case of a squash ball, it is hit by a racket).

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work