1. A student is investigating the factors that affect the size of the crater (hole) a ball makes when it is dropped into sand.

Plan an experiment which would enable you to investigate one factor which might affect the size of the crater.

The apparatus available includes

• metal balls of different sizes

• a tray of sand

  Write a plan for the experiment.

  In your plan you should:

• state which factor is being investigated,

• state the key variables that you would control,

• list any additional apparatus needed,

• explain briefly how you would carry out the experiment including what would be measured and how this would be done,

• state the precautions which should be taken to obtain reliable results,

• suggest a suitable graph which could be drawn from the results.

You may draw a diagram if it helps to explain your plan.