Science CT 2 Flashcards
What is a satilite?
A small object, orbiting a planet
Order the planets?
1- Mercury
2- Venus
3- Earth
4- Mars
5- Jupiter
6- Saturn
7- Uranus
8- Neptune
What is a sun dial?
A scale marked to show the movement of the sun using shadows. It ca tell the time as the shadow moves around it.
Some space telescopes?
hubble, webb
Moon phases in order?
new
waxing crescent
first quarter
waxing gibbous
full
waning gibbous
last quarter
waning crescent
new
Why do seasons happen?
the earths axis is tilted.
when the earths axis points towards the sun, it is summer in the northern hemisphere
when the earths axis points away from the sun, it is summer in the southern hemisphere
Characteristics of summer and the earth?
the northern hemisphere is tilted towards the sun.
sunrise: 03:44
sunset: 20:34
energy from sun: 195 J each second on 1m2
angle of sun above horizon at midday: 61 degrees
Characteristics of spring and autumn and the earth?
the northern hemisphere is not tilted towards of away from the sun.
sunrise: 06:08
sunset: 18:22
energy from the sun: 95 J each second o 1 m2
angle of sun above horizon at midday: 38 degrees
Characteristics of winter and the earth?
the northern hemisphere is tilted away from the sun.
sunrise: 08:16
sunset: 15:55
energy from the sun: 24 J each second o 1 m2
angle of sun above horizon at midday: 14.1 degrees
What is a magnet?
Metallic object that has the property to affect other metals through a magnetic field.
Magnets have two opposite poles (ends), one always moves towards the North Pole of the Earth and the other one, South.
SSP
South- seeking pole
NSP
North- seeking pole
Compus
an instrument that uses a magnet to point towards earths North Pole
Planet
Large body that orbits a star
Solar eclipse
when the moon moves in frount of the sun
lunar eclipse
when the earth moves between the moon and the sun
umbra
a full shadow
penumbra
a partial shadow
what way do magnetic field lines go?
North to South
How to calculate weight?
weight= mass(kg) x gravitational field strength (N/kg)
Constillations
an imagionary pattern of stars that people have seen.
stars arranged in a recognisable pattern
star
large balls of gas (plasma) which are very hot, emit light, heat and radiation and have very large gravitational field.
one light year
the distance travelled by light in 365 days
the speed of light in 300,000 m/s
the distance 10 million kilometer
galexy
a large, neutral grouping of stars and planets (and clouds of gas) usually with a black hole at the centre.
implosion
an object breaking down inwards, collapsing on itself
are triggered by forces like pressure, gravity or an explosion that starts the process.
they are physical processes overall
explosions
generally chemical changes (exceptions- eruptions)
release energy- heat, light, pressure, gasses.
reactivity
a chemical property of a substance.
the ability of a substance to participate in chemical reactions
To protect a metal from oxidation or corrosion, it can be coated with:?
- a protective lager= e.g paint, oil
- a sacrificial metal= a more reactive meal that oxidises quickly and forms a layer of oxide which is stable and prevents oxygen from reaching the metal underneath
protons
positive electric charges- found in the nucleus
neutrons
neutral- found in the nucleus
electrons
negative charges- found orbiting around the nucleus at defined distances
How many electrons can fit onto a shell?
1= 2 electrons
2=8 electrons
IONS
when an atom loses or gains electrons
metallic bonding
the delocolised electrons are still attracted by the positive charges of the ions (in fixed positions). this is electrostatic attractioln is strong
IONIC BONDING
the bond formed by the electrostatic attraction between a positive ion and a negative ion
Positive IONS
lose electrons
METALS lose electrons to become positive ions
Negative IONS
gain electrons
NON-METALS who accept electrons to become negative ions
energy
the ability to do “work” or change.
NOT created or detroyed it is TRANSFERRED
exothermic
energy is given to the surroundings
heat the environment
endothermic
cool down their surroundings
endothermic examples:
ice packs
sports indary cool packs
evaporation
exothermic examples:
all combustion reactions
freezing and condensation
