Description of the Experience
In the beginning it must be said that the general education courses including the physics are on the outskirts of interest in the specialized schools. Even bigger problem is that the topic to which I had a few years ago three classes I must teach now in one lesson only. The students come from elementary schools without basic knowledge of physics. They perceive physics only as a school subject. They are scared of the formulas and counting examples. It is necessary for them to understand that almost everything that is happening around us and in us is "physics", from breathing to death.
Free fall is uniformly accelerated motion and even the whole point is said in the name already they still can not explain what this movement is. Luckily I have to just let go off the chalk and they can see it. It is the easiest demonstration. Then I give examples of relationships between distance and speed over time of the freefall. They have to remember the existence of gravitational acceleration g and its value. The connections are easy, the longer body falls, the more speed it gives. Bigger problem is to understand that the path grows with the square of the time, so if time is increased twofold, the path is extended four times. The gravitational acceleration was measured by Galileo Galilei. It is said that he was throwing together with his students various objects from the Leaning Tower of Pisa and measured the time with his own pulse. It is particularly important when these facts are noted that the environmental resistance - usually air is usually not considered since its value is too small.
Galileo is unofficially considered to be the first physicist in the history of science. His ideas were at his time unacceptable to the omnipotent Catholic Church. He constructed a telescope by himself and headed it to the Moon, to show that there is no sign of life there. At that time the idea was applied that there are the “moon people” living in the Moon. To this telescope he was inviting priests to see by themselves, but they were afraid of the tool. If he hadn’t had influential defenders of the Catholic celebrities on his side, he would end up burned. Even though he had to withdraw his thoughts and opinions and declare that it his thinking and ideas were wrong. He was placed among heretics. He was punished “only” by a lifetime house arrest. He was not allowed to communicate with anyone but this command he successfully bypassed. He was never married but had two daughters, which was at that time totally unacceptable, because he never married their mother.
Within the department, which I teach, it is interesting to explain that the car head-on collision with a fixed obstacle has the same effect as if the car was dumped from a height to the ground. It is clear from the law of free fall, and it can be easily calculated.
It is shocking when students see that in an environment where there is vacuum, lands a lead bead and a feather at the same time. A Newton's tube is used for this experiment.
I assess this experience positively.
"And yet it spins. " was allegedly Galileo’ s last sentence before his death.
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