The Night Sky
What is the name of the Star closest to Earth?
The Sun
What TWO things determine the strength of gravity?
1. The distance apart 2 objects with mass are
2. The size of the objects
What is the orbit time for Earth?
365 and a quarter days.
What is the difference between renewable and non-renewable energy?
Energy sources that either cannot be replaced or take millions of years to do so are known as non-renewable energy sources.
Renewable energy sources can be used over and over again.
What do you call a model of the universe that has Earth as its centre?
Geocentric Model
List the 4 terrestrial planets in order from the Sun
Mercury, Venus, Earth and Mars
Explain why your aren't being pulled towards a wall despite there being a gravitational attraction between you and it?
mass of the wall is much less than the mass of the earth. Therefore wall attraction is not noticeable compared to earth's gravity
In which city will the sun rise first in Perth, Cairns, Adelaide, or Hobart? Explain why.
Cairns, because due to the direction the Earth is spinning, the Sun appears to rise in the East and set in the West.
Provide 2 advantages of Wind energy.
1) It is a renewable resources which means it doesn't use up any substances to create electricity.
2) It can generate electricity day or night, as long as there is wind.
What is the formula for weight?
Weight = Mass x Gravity
Provide and example of both an artificial satellite and a natural satellite.
Artificial = Space station, Hubble telescope etc
Natural = Moon, asteroid, planet, comet
How long does it take for the Moon to orbit around the Earth?
•The Moon takes 27.3 days to orbit the Earth
•The Moon also takes 27.3 days to complete 1 full rotation on it axis
How many degrees is the tilt of the Earth's axis?
23.50
Give 2 reasons why you can collect more solar energy in summer than in winter.
1) the days are longer
2) the earth receives more direct sunlight during the summer.
What is the difference between a waxing crescent and a wanning crescent?
Waxing crescent is when the moon is getting bigger, wanning crescent is when the moon and getting smaller.
What is the difference between a meteoroid, meteor and meteorite?
•Meteoroid – small rock traveling through space
•Meteor – Falling rock in the Earths atmosphere (looks like blazing fireball)
•Meteorite – The part of the rock that reaches the ground
Explain the difference between a solar eclipse and a lunar eclipse.
•A solar eclipse occurs whenever light from the Sun is blocked by the Moon, casting a shadow onto Earth.
•During a lunar eclipse the Earth blocks light from reaching the Moon
In which season are the days the shortest?
What 2 energy sources do Iceland use to power their entire nation?
Hydroelectricity and Geothermal energy.
Why can we not see the other side of the moon?
The orbit time and rotation time of the moon is exactly the same.
A type of nuclear reaction called a fusion reaction converts which 2 gases on the Sun?
Hydrogen and Helium
Explain how the moon creates a high tide on Earth at the 2 opposite sides.
The moon's gravitational force pulls the water on Earth towards it creating a high tide. On the opposite side of the Earth is also a high tide due to the Earth being pulled slightly towards the moon.
How does the tilt of the Earth create seasons as it rotates around the Sun. Explain how some parts experience summer. and others winter.
As the Earth rotates some parts of the Earth point towards the sun, exposing them more so that the sunlight is more concentrated – these parts experience summer.
A disadvantage of tidal energy is that we must place the turbines around port areas which don't allow big ships to pass by. Explain why we can not place the turbines out in the middle of the ocean?
The tidal energy turbines need to be connected back to the power grid, therefore it would be very expensive and difficult to connect the turbines back if there where out far in open sea.
Would I jump lower on Saturn or Jupiter? Why?
Jupiter because it is slightly larger than Saturn; the larger the planet, the more gravity (so you weigh more).