space Flashcards
what is a scalar quantity ?
only has size
what is a vector ?
has size and direction
what is distance ?
SCALAR -how far something has travelled and is measured in meters
what is displacement ?
VECTOR- direct distance from the starting point to the finishing point in a stated direction measured in meters
what is speed ?
SCALAR - distance travelled per unit of time
what is velocity ?
VECTOR -displacement travelled per unit of time YOU NEED DIRECTION
what are the 5 scalar quantity’s ?
distance, speed, time, mass, energy
what are the 5 vector quantity’s ?
displacement, velocity, acceleration, force, weight
why does a projectile follow a curved path ?
due to constant horizontal velocity and constant vertical acceleration due to the force of gravity
in vertical motion what is Uv and a ?
Uv = 0 ms/1 a = 9.8 ms/2
what is a satellite ?
something that orbits the earth but is essentially a projectile
how does a satellite orbit ?
it has a constant horizontal velocity (no air friction) and a constant acceleration towards the centre of the planet because of its weight. this results in a projectile curve. satellites only remain in orbit because of gravity.
what is earths natural satellite ?
moon
what is the period of a satellite ?
how long it takes to complete one orbit
what does the period of a satellite depend on ?
the altitude because the higher the it is the longer it takes to complete one orbit so period increases with altitude
what is a geostationary satellite ?
stay above the same point at the earths surface, they orbit above the equator and and travel in the same direction that the earth travels.
what is the period and the altitude of orbit for a geostationary satellite ?
period- 24 hours
orbit at - 36 000 km
name 5 benefits of geostationary satellites
communication, GPS, weather forecasting, scientific discovery, space exploration
name 3 challenges of space travel
- travelling large distances
- manoeuvring in a zero friction environment
- maintaining sufficient energy to operate life support systems (solar panels)
name 4 risks of space travel
- high fuel load on take-off so a fault could result in huge explosion
- exposure to radiation from cosmic waves
- different pressure inside the space craft and in space
- re-entry to the atmosphere causes immense heat from friction
what is newtons 3rd law ?
if A exerts a force on B, the B exerts an equal but opposite force on A
example of newtons 3rd law -
rocket exerts a force on the gases downwards
the gases exert a equal and opposite force on the rocket upwards
when was the big bang ?
13.7 BILLION years ago
what is a planet ?
a large body orbiting a star which has been rounded by its own force of gravity
what is a dwarf planet ?
new planet where it’s orbital path is not clear of debris
what is a exoplanet ?
out with our solar system
what is a asteroid ?
an irregular shaped rocky object in orbit around a sun or star
what is a moon ?
a large body orbiting a planet and a natural satellite of a planet
what is a star ?
a giant ball of hot gas producing energy through nuclear fusion
what is a sun ?
a star with planets orbiting it
what is a solar system ?
the system of a sun and its orbiting planets
what is a galaxy ?
a large collection of stars (milky way)
what is a universe ?
all of space and everything in it
what is a light year ?
a unit of distance. how far light travels in one year
how many days in one year ?
365
when you calculate the distance for a light year what is the time ?
365 x 24 x 60 x 60 (number of seconds in one year)
why do you need different types of telescopes ?
because they can observe space as different frequencies of radiation so they require different detectors
why do we use telescopes ?
to get detailed information of the universe in all wavelengths
what is the continues spectra produced by ?
produced by solids, liquids and high pressure gases. there are no gaps or breaks
what is the line spectra produces by ?
produced by low pressure gases
what are the colours of the continues spectra ?
violet , indigo, blue, green, yellow, orange, red (visible light)
