When you observe the world and see something that you don't understand, you make a hypothesis that you try to prove. this either fails so you make a new hypothesis, or it is proven to be correct.

Just like the water cycle, rocks undergo changes of form in a rock cycle. A metamorphic rock can become an igneous rock, or a sedimentary rock can become a metamorphic one. Unlike the water cycle, you can’t see the process happening on a day-to-day basis. Rocks change very slowly under normal conditions, but sometimes catastrophic events like a volcanic eruption or a flood can speed up the process. So what are the three types of rocks, and how do they change into each other? Keep reading to find out!

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it