Like other viewers, I'm very grateful to your series of uploads and feel very fortunate to be able to watch them! I had a thought that perhaps adding a more accurate set of subtitles than the current auto-generated one could aid more non-native English speakers (like myself) in understanding this excellent lecture, so tried my best to write a set and submitted it several minutes ago. May I please welcome any other RU-vidr who could view it or the Channel's manager (if luck and time allow) to have a review, so that perhaps after it's enhanced/approved it can be publicised and used? Thanks for reading!
.I would not say "and that is that" about magnets consists of small magnets. Magnetisme is the kinetic energy of the electric field and that is that! . If you send an electric charged particle out in space you and everybody that is not moving relative to you can measure a magnetic field around it. But somebody moving with the particle cannot measure any.
Superb video.... I love to see the magnetic field lines formed by the iron filings.. this is the things we always read in books but never practically see...
So i guess it correctly that old days molten steel were under the magnetic influence of earth magnet, so while cooling the alignment made the steel permanent magnet. But what could have influenced earth's magnetic field, is it sun
CHANAKYA SINHA, I think you are correct, but the early stages of the Earth’s development are still something of a mystery. The Sun is, indeed, a massive magnet. It is not yet known exactly what the influence of the Sun’s magnetic field is, but I wonder if it influences the Earth’s climate and weather in some ways.
@@thispersonwriting1889 considering sun, it has so much randomness in their molecular energy that even for a single nanosecond, there is one out of infinite possibility that all electrons and plasma will have motion such that it can create magnetic field ... What else could be possibly generating that field
The Earth's magnetic field is created by flows of molten iron-nickel alloy in the outer core. The flows are driven by convection due to heating from radioactive decay in the core. The sun's magnetic field has almost no effect on Earth: at this distance it's very weak. To magnetise something the size of the core (1600 million million million tonnes of metal) you would need a very strong external field: much stronger than the sun's field and strong enough to cause problems at the surface.
@@DANTHETUBEMAN A molten metal cannot be a permanent magnet, that is true, but a molten metal can create a magnetic field. By analogy, copper cannot be a permanent magnet, but it can create a magnetic field.
