02.12.19-02.13.19
Experiment Leaders: Elizabeth and Tommy
February’s visit gave students a better understanding of the Earth’s magnetic field and how it relates to electricity. We first began with a presentation discussing the importance of Earth’s magnetic field and how it allows for navigation and even causes the Northern Lights. We gave a demonstration, dropping strong magnets through a copper tube. This showed that while the copper tube was not magnetic, it caused the magnets to drop slower through the inside of the tube than on the outside. This is caused by induced currents within the tube, with the magnetic field opposing the force of gravity.
To give the students a more interactive understanding of electromagnetism, we did two experiments. In the first, we created an electromagnetic induction motor, in which the students used copper wire, magnets, battery packs, and alligator clips to create a motor similar to that of blenders or fans. With copper wires suspended in metal brackets attached to the battery packs via alligator clips, magnets held close to the wire caused the wire to spin very fast!
In our second experiment, we used potatoes and electrodes to convert chemical energy to electrical energy in order to power an LED light. When copper and zinc electrodes were places together in a potato, the students could measure the voltage and current through the potato using a multimeter. Students also examined the effect of electrode distance on voltage and current. Through adding more electrodes in series, the students could generate enough voltage to light an LED light. With higher voltage, colored lights, like green and blue, could fluoresce! The students enjoyed the opportunity to experiment with different combinations to light different colored lights or even try to light multiple lights.
Overall, the students (and mentors!) enjoyed experimenting with magnets, potatoes, and LED lights, and we can’t wait to go back next month!