Revision - Universe, Earth and Moon
1. Stars produce the energy via the process called ………………
2. In nuclear fusion, two hydrogen atoms are fused to form a …………..atom
3. A dying star collapses in onto itself and a massive explosion occurs. This can only
occur in a ………………..
4. In the electromagnetic spectrum …………. has the longest wavelength while ……… has
the shortest wavelength.
5. Flame colours will origin when electrons return from an ………..state to …………ground
state.
6. A star’s spectrum is mainly determined by its ………………….
7. Each element emits and absorbs a unique combination of colours of light, which are
also called as specific ……………….
8. Atomic number is the number of ……………… in a nucleus.
9. Big Bang is not an explosion, but more a ………………….
10. Four fundamental forces emerged and begin to influence particles in the ……………era
11. In particle era, some energy is permanently converted into mass to form
…………which will then go on to build protons, electrons and neutrons.
12. The scientist named …………. discovered that almost all galaxies are moving away
from us and from each other.
13. Hubble observed that light coming from almost all galaxies was …………….
14. ……………………… is the remains of energy created just after the Big Bang.
15. The cloud of nebula formed a ………………..disc with its rotation.
16. Growth by gradual accumulation of additional layers of matter is called as………….
17. The core of the terrestrial planets are made up of ……………….
18. The………………. represents the boundary between terrestrial planets and gas giants.
19. The separation of earth into different layers based on density is called as ………….
20. Moon is formed when another protoplanet called …………….collided with the earth.