People love negative results. But proving something doesn't work requires proving you didn't stuff up the implementation. That is amazingly hard, and about 10x more work then showing a positive result.
For example what you're talking about with magnetism isn't a negative - you can prove that an effect is bounded by the lower limit of accuracy of your instruments. Physicists do this all the time, because it's the correct way to phrase the result. I'll not to speak to the quality of your teachers though.
People love negative results. But proving something doesn't work requires proving you didn't stuff up the implementation. That is amazingly hard, and about 10x more work then showing a positive result.
For example what you're talking about with magnetism isn't a negative - you can prove that an effect is bounded by the lower limit of accuracy of your instruments. Physicists do this all the time, because it's the correct way to phrase the result. I'll not to speak to the quality of your teachers though.