P 8 Revision

Complete these sentences on the LIFE CYCLE of a STAR...

Cloud of dust is called a n_____. The force of g______ pulls d___ and g__ together.

Protostar : -The Star gets d_____ and the t__________ rises and more particles collide. The temperature gets h___ enough and h_______ undergoes n______ f_____ to form h_____. This gives out a huge amount of e_____.

Complete these sentences on the LIFE CYCLE of a STAR...

The main sequence - Long stable period where outward p_______ caused by n______ f____ that tries to e_____ the star. This b______(s) the force of g______ pulling everything i_____(s). (Last several billion years).

Hydrogen begins to run out - Star s____(s) up to a r__ g____ or s____ r__ g____. It is red because the surface c___(s). Fusion occurs of h_____ and heavier elements created in the c___.

How is a WHITE DWARF created?

• Because it becomes unstable and ejects its outer layer to form a white dwarf

• Because it cools down, emits less energy. When no energy is emitted

How is a Black DWARF created?

• Red Giant cools down, emits less energy, when no energy is emitted black dwarf is created.

• Red Giant becomes unstable and ejects its outer layer to form a white dwarf

Complete these sentences on SUPERNOVA...

Star g___(s) brightly again as more f_____ occurs they e_____ and c______ several times (forming elements). E______ in a supernova forming elements __+, new stars and plants.

Which of these describes a NEUTRON STAR?

• Outer layer of dust and gas into outer space leaving the very dense core

• A super dense point in space that not even light can escape from

Which of these describes a black hole?

• A super dense point in space that not even light can escape from

• Outer layer of dust and gas into outer space leaving the very dense core

Complete these questions about ORBITS: -

Gravity is a force that c_____(s) o____(s).

Planets move a_____ the sun in a c_______ orbit.

Object travelling in a c_____ is constantly changing d________, which means it is constantly changing v_______ (NOT S____).

To accelerate there must be a f____ acting on it directed towards the c_____ of the circle.

Force would cause the object to f___ towards what it is orbiting, but because it is already moving it just changes d________.

Object keeps a___________ towards what it is orbiting, but the instantaneous v_______ keeps it in a c_____.

Force which does this is provided by g______ between the p_____ and the s__.

Complete these sentences about ORBITS...

Size of an orbit depends on s____.

The closer you get to a star the s_______ the g____________ force. A stronger force means the f_____ the orbiting object needs to travel to r_____ in orbit. If an object is in a stable orbit and the speed changes, the s___ of its orbit must c_____ as well.

Faster = S______ R_____

How are all the galaxies moving?

• Towards each other

• Away from each other