s2 term 2 Flashcards
what are the 8 planets in order of closest too the sun
mercury
venus
earth
mars
jupitar
saturn
uranus
neptune
what is our galaxy
the milkyway
how many galaxies are there
100 billion
what is the structre of the earth
inner core
outer core
mantle
the crust
what is the inner core made of
solid iron
what is the outer core made of
magma liquid
what is the crust made of
solid rock
what is the earths crust made up of
huge slabs of solid rock that are floating above the mantle
what are tectonic plates
huge slabs of rock
how are earthquakes and volcanoes made?
the tectonic plates are slowly moving the area where 2 plates meet make them the tectonic plates fold under each other
what are 2 plates moving apart called
constructive plates
why are constructive plates called that?
because when they move apart magma shoots up and makes new land when it solidifys
what are tectonic plates called that are moving towards eachother
destructive plate boundary
what are the 3 types of volcanoes
dormit
extinct
active
what is an extinct volcano
a volcano which have not errupted for millions of years and will never agaiin
what is an active volcano
volcanos which regularly errupt
what is a dormant volcanoes
volcanos which have not errupted for many years but could still errupt at any time
what is the most dangerous type of volcano and why
dormant volcanoes
they are difficult to predict and they errupt with a huge explosion because it has been building up for years also because people live close to these volcanoes
what happenes when a dormant volcanoe errupts
huge explosion of ash poisones gas and steam
a big cloud covers the sky
lava bombs shoot out
lava flows from the volcanos
often melted snow can cause floods
why do earthquakes occur
when two tectonic plates slide past eachother or are colliding
the plates can get stuck on each other and then suddenly jerk apart
what are primary effects of an earthquake
buildings collapse
roads and railways destroyed
services hospitals and schools destroyed
people injured and killed
what are secondary effects of an earthquake
millions homeless
buisness destroyed [no income]
lack of food and clean water
shortage of healthcare
disease
what are seismic waves
the shock waves/vibrations which are sent out from the earthquake
what is the focus of an earthquake
the point underground where two plates jerk apart seismic waves are sent from this point
what is the epi-centre
the point on thresurface directly above the focus the effects of the earthquakes are most severe at this point
why are earthquakes more deadly in poor countries
they have poorly made building that collapse
they have no warning system or high tech to send the warnings too
they have no emergency supplies like food and water stored
they wont have rescue teams avalible
they might not have enough money to re-build
what is pangea
it was earth millions of years ago when all the continents joined together calling it pangea
what is continentiol drift
its when the continents moved away from eachother
what is the ring of fire
the ring of fire is a ring of volcanos around the pacific ocean
what causes seasons
the earths axis is perpendicular therefore differnt parts of the globe are oriental towards the sun at differnt times a year
how does spring happen
the sun is over the equator so both the north and south poles are in equadsant
