Task 6

Materials and tools for a working group:

various magnets, metal paper clip, ruler

In the following task, pupils will address a research question to determine whether the same magnet always attracts the same object from the same distance. As with other research tasks, it is important to emphasize the research question: Does the same magnet always attract the same object from the same distance? Unlike the previous research task, this is the procedure given in the form of a pre-prepared table in which the pupils are to complete the results. The discussion of the procedure proceeds with the emphasis on the practical implementation of the measurement of the distance from which the magnet attracts the object. For example, it is important to perform all measurements on the same substrate; the object must always point to the magnet in the same way; the magnet must always approach the same side and the like.

The task of pupils will be to measure the magnitude of the magnetic field of two different magnets by a predetermined procedure. The goal of the task is to develop the ability of pupils to process data into results and subsequently to relevant conclusions (i.e., data anchored in conclusions). They learn to work appropriately with the identification of the exception and the rule for repeated measurements, thus clarifying the very importance of carrying out repeated measurements.

The teacher explains the procedure to the pupils. To position 0 on a ruler placed on a smooth surface (on the bench), attach one of the objects to be used for observation (paper clip, coin - see table in task 6 in the worksheets for the pupil). They magnetically approach the object along the ruler and watch when the object is attracted by the magnet. They measure the distance and write it in the table. The measurements are repeated 4 times for the same object and the same magnet. Then the measurements are made for the second magnet, again 4 times. They also make measurements with a coin and another item they choose.

The task for pupils is to review the table and think about what and how to measure so that they can add data to the spreadsheet. Subsequently, they carry out observations, adding to the table two other arbitrary objects with which to measure. They must be objects that are attracted by the magnet. The teacher observes how they progress in the work of the pupils and, if necessary, warns the pupils in the groups to make observations so that they can trust the results.

After the measurement is completed, it is the task of the pupils to answer the questions under the results table. The questions prompt them to identify the rule in the data they have acquired and guide them to use the data to support their conclusions and other generalizing statements.

The teacher can initiate the results discussion. For example, it invites one group to present their results, while the task of the other groups is to compare their own research results with those presented by their classmates and express the similarities and differences found. If different results are found, the teacher should endeavor to identify with the pupils the reason for obtaining other results and thus justify the difference.

During the conclusion making, the teacher draws attention to comparing the data obtained with the same magnet and the same object (repeated measurements). If there is a big difference between the measured data, the measurements should be repeated and data that have a very high or very low value from the data set should be excluded and justified by a measurement error (so-called error acceptance, exceptions). By comparing the results, pupils should find that for different objects and the same magnet the measured values are different. However, if one object has a larger magnetic field (attracting objects from a greater distance), the values measured for the same object are always greater in this magnitude than the second magnitude (rule recognition, searching for a research question in the data).