Elephant Feet

Aims and objectives
This activity aims to illustrate and explore the relationship between weight, area and pressure by answering the question, ‘I wonder what it feels like if an elephant steps on your toes?’. The resource uses guided student research, note taking and virtual experimentation. There is a close link between the science and maths programmes of study.

Previous knowledge
Students will need to have a reasonable grasp of mathematics (e.g. simple algebra, converting m 2 to cm 2, using Pi etc.) and scientific principles of mass, gravity, Newtons etc..

In the classroom
When starting the activity make sure that the students click on the Start button, put their name in the box and click Enter. This will activate the notes page which will allow students to keep notes and records of their findings as they try to answer the questions about the elephant's foot.

1. Will the elephant squash your foot?
2. What is pressure?
3. How are weight and pressure related?

Students work their way through the questions and activities to try to find the answers. When they think they have an answer, encourage them to discuss it with you (remember to ask them for their evidence).

The issue here is the relationship between weight, area and pressure. Clearly elephants are very heavy, so we might expect the person's toes to be completely squashed. However, the bottom of the elephant's foot also has a large surface area.

What will determine the amount of damage to the toes is the pressure from the elephant's foot. That will depend on the area of the elephant's foot as well as its weight, whether the rest of its foot is in contact with the ground and how many feet it is standing on. Our estimate is that it would be painful but probably would not completely crush your toes. We haven't tried this!

This activity aims to help the learner answer the questions being asked on the front page of the resource. To achieve this there are on-line information sources, research resources that take you out on to the World Wide Web, some interactive activities and some classroom based activities that can be used to assist in finding answers. Most of these activities link back to the classroom and on occasions require data to be recorded and graphs to be plotted.

The activity is best suited to group working over a number of lessons. Periodically, groups can be asked to present their findings to the rest of the class where more open discussion can take place. This will provide assessment opportunities and will assist teachers in identifying areas where misconceptions need to be addressed or further support/teaching input needs to be developed.

Throughout the activity there are also opportunities for modelling some of the principles with either whole class demonstrations/investigations or, resources permitting, small group tasks. These mini-activities are important as they also support the development of planning and the carrying out of scientific tests, identifying variables to ensure tests remain ‘fair’ and the gathering of accurately measured data for later analysis (see worksheet below).

 Support materials description: Resource type: The Elephant_feet.pdf contains a data collection chart to support the part of the elephant activity where students model differing masses and areas for a virtual elephant. The worksheet contains instructions as well as extension ideas for making predictions and testing hypotheses. Elephant_feet.pdf

Curriculum references
Science – KS3:
Sc1 1b; 2a, b, g, i, j, l, o p
Sc4 2g

Mathematics – KS3:
Ma2 1a, f, j, k; 4a
Ma4 1a, c, d, e, f, g, i; 3a, b; 4a-h; 5a-e