As a metal ball falls through a liquid, it experiences a frictional force from the liquid that opposes the motion of the metal ball. Plan an experiment to determine the relationship between the density of a liquid contained in a measuring cylinder and the average speed of a metal ball falling through the liquid from the surface of the liquid to the bottom of the cylinder. The average speed of the ball is calculated using the equation: average speed = distance travelled / time taken The arrangement of the apparatus is shown in Fig. 4.1. [Figure 4.1] The apparatus available includes: • a measuring cylinder • a metal ball • a selection of different liquids whose densities are known. You are not required to do this experiment. In your plan include: • any other apparatus needed • a brief description of the method, including what you will measure and how you make sure that your measurements are accurate • the variables you will control • a results table to record your measurements (you are not required to enter any readings in the table) • how you will process your results to draw a conclusion.

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