Task 8

Materials and tools for a working group:

solar cell, motor with propeller, 3 wires (eg crocodile clips with cable), switch, table lamp with sliding head, ruler, colored foil (yellow, red, blue)

Other electrical sources than batteries can be used to create a simple electrical circuit. In this task, pupils create a simple electrical circuit again, but now they use a solar cell instead of a battery. In this task, pupils should take into account the lessons learned from the previous activity – the electrical circuit will operate when it is closed. The aim of the activity will be to connect individual components (conductors, motorcycle with a helicopter, solar cell) according to the schematic representation in task 8. Subsequently, some groups can spin the motorcycle helicopter – depending on the room lighting. In the event that no helicopter moves, the pupil teacher discusses how solar cells (collectors, power stations) work, which we need to use them. The aim is for pupils to come to the conclusion that light will be the source of energy in this case.

Pupils focus on examining the effect of light on the functionality of solar cells, as outlined in the eighth task guide. Relatively strong incandescent bulbs or halogen bulbs with which it is possible to generate sufficient electric power to spin the motor (suitable lamps are not suitable) are suitable for the investigation. The first research task is to find out whether the distance of the light source from the solar cells affects the spinning of the motor with the propeller, i. whether or not this distance depends on how much electricity is generated (8a). After giving a research question, the teacher guides the pupils to make predictions that they put in the table. Pupils also think about specific distances (10, 20 and 30 cm). For example, if they think that such differences in the source distance from the solar cell do not affect the motor, but more distances do, they will say so. Then, the pupils are checked for predictions and recorded the observation results in the verification section. When verifying predictions, the pupil‘s teacher points out that they should verify precisely, i. the only feature that changes is the distance of the lamp (s) from the solar cell. Neither the light source nor the solar cell must be inclined, the light must fall perpendicular to the solar cell in all three cases. Please note that the article may overheat if the lamp bulb is placed too close.