Everything1 Flashcards

Question

Unstable nuclei are the reason of radioactivity This is due to

Answer 1

Too many neutrons or protons Large size.

Answer 2

Raging Martians Invaded Venus Using X-ray Guns radio waves radiation, microwave radiation, infrared, visible light, ultraviolet, X-rays, and gamma rays

Answer 3

The activity of a radioactive source is the number of unstable nuclei that decay every second Units Becquerel

Answer 4

The activity of a radioactive source is the number of unstable nuclei that decay every second

Answer 5

Count rate is The number of decys recorded each second by a detector

Answer 6

Count rate is The number of decys recorded each second by a detector

Answer 7

A satellite is something or anything that orbits a planet

Answer 8

Like the moon and it is NOT man made

Answer 9

Something that orbits a planet like communication pr orbital telescopes which ARE man made

Answer 10

Astroid are mostly made from rock and metal and are found in the asteroid belt COMETS are made of ice and dust they do orbit the sun and orbit ellpitically and are at the outskits of the solar system

Answer 11

Galaxies are a collection of billions of stars called star systems Ours is the milky way The UNIVERSE IS A VAST AREA SCATTERED WITH GALAXIES AND GALAXIES HAVE BILLIONS OF STARS AND SOLAR SYSTEMS They are held by gravity

Answer 12

Starts as a nebula :a cloud of dust and gas Then over time gravity pulls dust and gas together to become a Protostar as particles collide and join the protostar and gets bigger and force of gravity gets stronger and attracts more dust and gas Then gravity squeezes it and makes it more dense and then there are more frequent collisions then when temperature and pressure gets high enough hydrogen nuclei fuse to form helium nuclei this is called nuclear fusion and this gives out lots of energy and becomes a star

Answer 13

The outward pressure caused by the energy released is balanced by the inward pressure of gravity This allows for a long stable period where it lasts for billions of years Eventually the star will run out of hydrogen and wont be able to complete nuclear fusion and then inward pressure of gravity contracts the star inito a small ball and then it gets hot and then nuclear fusion starts causing it to expand and this time round it will form heavier elements

Answer 14

If the star was a small to medium star it will form a Red Giant After time ot becomes unstable and and expels dust and gas layers This then leaves a hot dense solid core amd is called a white dwarf This gets cooler and darker and becomes a Black Dwarf

Answer 15

If the star was really big it would turn to red super giant After time it starts to shine brightly again as it undergoes more nuclear fusion After many cycles of expansion and contraction it explodes and it becomes a supernova And then it forms elements heavier than iron that get ejected across the universe If it was just big it would become a neutron star But if it was massive it would become a black hole

Answer 16

An object travelling at a certain velocity will continue to travel at that velocity.Unless acted upon by resultant force

Answer 17

Acceleration = change in velocity / time