O level Physics

Ppl are asking about star formation so here is it:
1. After the big bang there was "dust" everywhere with hydrogen.
2. These dust clouds are called nebula.
3. V know that more mass creates more "deep" curvature in space time known as gravity.
4. So the concentrated dust and hydrogen particles had more gravity than others.
5. Thus they attract the dust and hydogen particles.
6. A lot of hydrogen particles came together creating immense gravity.
7. The gravity forced the hydogen atoms to fuse together and form a heavier element known as helium.
8. This fusion caused a lot of energy being produced in the form of light and heat.
9. This tremedous energy also produced presure which makes the star to go "outwards".
10. On the other hand, the gravity makes the star to go "inwards".
11. Thus a stable shape and structure of a star is created which is kind of round.
12. The star continue its life.

PHASES OF ITS LIFE:

13. Eventually the fuel is consumed.
14. Less energy is formed.
15. Star will produce less heat and light.
16. Notice that less pressure is produced.
17. Pressure=pgh
18. As the pressure reduces, so should density.
19. Mass will remain same so the volume increses.
20. The star becomes red giant.

FOR SMALL STARS LIKE SUN

21. The fuel continue to reduce.
22. The star expands more and seem like a cloud of dust and known as Planetry Nebula.
23. Eventually, the fuel almost ends
24. And gravity overcomes
25. Thus the star becomes very small with very very less light known as White Drawf.
26. We will see this happening to our Sun in the next 5 billion years.

FOR GIANT STAR HAVING ATLEAT ×3 MASS OF THAT OF SUN

27. This also faces the same life stages as that of other stars but the red giant is bigger depending on the size of star.
28. The fuel ends and the star has very very strong gravity.
28. The gravity overcomes the pressure very quickly.
29. The contents of the star which is hydogen and helium also faces effect of gravity and further fuses and creates more dense elements like iron etc.
30. A big explosion occurs due to the contacting of a huge star very fastly.
31. This explosion is called Super nova
32. These elements shoot out at 10% of the speed of light.
33. U must have seen that video in which rubber band crush watermelon and it is shooted out. Same is which stars, gravity is rubber band.
34. These elements created Earth and other sruff.
35. As the gravity was first "distributed" in the whole star so it created a less curvature in space time which is weak gravity.
36. But now the whole gravity is concentrated in one small place where there is almost no content.
37. So this thing is called black hole.
38. Now a smaller area has a large gravity which is greater space time curvature.
39. As there is nothing in the black hole so it cant be seen.
40. It can however be observed by coming and gathering of light of star in one place.
41. The very center is called singularity.
42. The boundry, in which if anything enters including light, can not escpe, is called Event Horizon.
43. It emits x rays and gamma rays which can be detected to know the location of a star.

This was what is star formation and its life stages.
Sorry 4 any spelling error.
Hope it helps.
If u have any question, feel free to ask😉