Task 4

Materials and tools for a working group:

various long boards (50, 80, 100 and 120 cm), cube (30 cm high, base to create inclined plane), dynamometer, bucket or other object suitable as a load

In the third task, pupils find that by moving the material on an inclined plane, we spend less effort on lifting the load comparing pulling the load directly without using an inclined plane. Task 4 is aimed at detecting differences in effort using differently inclined planes. The aim of this activity is to develop the capability to measure and use the measurement result to express an objective (fact-based) conclusion. The verification process is given again, so it is advisable for the teacher in the initial discussion to make sure that pupils understand the principle of the method of prediction verification. If the pupil does not understand the principle of the proposed verification procedure, he/she will implement the procedure itself, but will not be able to relate the result of the observation to the established research question, respectively. with a presumption.

Differently inclined planes are createdusing differently long boards (50, 80, 100 and 120 cm), using the inclined planes we want to get the load to the same height (30 cm). It is advisable to adjust the height and length of the inclined planes so that the pupils find differences when pulling a particular load. Therefore, the use of inclined planes must be tested in advance with specific materials, and an appropriately heavy load should be selected, as well as an appropriate scale.

Pupils make measurements and record numeric values (from the dynamometer) into the appropriate cells of the table. They repeat the measurement three times for each inclined plane in order to be sure that they have measured the data correctly. If one of the three measured values is significantly different from the other two, pupils should exclude the measurement from reasoning because of a probable measurement error. In this way, we develop the ability to measure, which leads pupils to make objective judgments and teaches them the precision typical of scientific research. Then pupils try to reach a conclusion and support the stated conclusion by comparing the numerical values (they argue with the measured data in the sense of the conclusion). The conclusions and their reasoning by means of measured data will be entered in the section for the result of the observation.