p.21-27 Flashcards
What is the main purpose of earth’s Atmosphere
Insulates the earth from the extreme temperatures of space by keeping the heat inside the atmosphere
Other than keeping the heat trapped inside, what other role does the atmosphere fulfill
it blocks much of the Sun’s incoming ultraviolet radiation
Truth or False : Oxygen is the main component of our earth’s Atmosphere
FALSE, it is actually Nitrogen
What percentage of the earth’s atmosphere is composed of Nitrogen
78% of earth’s atmosphere is made of Nitrogen
Name the 4 main gaseous elements that make up our earth’s Atmosphere
- Nitrogen
- Oxygen
- Argon
- Carbon dioxide
What percent of earth’s atmosphere is made of oxygen
20.9%
Carbon dioxide, the gas causing much of the earth’s global warming, represents what percent of earth’s atmosphere?
only 0.03%
what is the state of matter of all the elements that compose the Atmosphere
they are gases, that is why we call the atmosphere a gaseous layer
What percent of earth’s atmosphere is composed of Argon
0.90%
What are the 3 energy sources that we can harvest from earth’s atmosphere
- Wind Energy
- Solar Energy
- Tidal Energy
As wind blows it holds energy, what form is that energy in?
when the wind is blowing, it is holding Kinetic energy (the energy of motion)
In which direction does air move when it creates wind
It always moves from an area of high pressure to an area of low pressure
fill in the blank : Wind is the movement of air from an area of _________ pressure to and area of __________ pressure
From and area of high pressure to an area of low pressure
As we know, when wind blows, it holds kinetic energy, how can we harvest this energy to use it in powering our needs
We must transform this energy from kinetic energy to a more useful form of energy, either mechanical or electrical
What is the goal of a wind turbine
To transform wind’s kinetic energy into electrical energy
describe the step by step method we use to harvest the Wind’s energy
- Wind hits turbines blades (kinetic energy of the wind)
- this turns the blades of the tubine (mechanical Energy)
- the turbine is attached to a generator and when we soin the turbine, it spins the generator (mechanical energy)
- the generator creates electrical energy when it is spun (electrical energy)
Name the advantages of Wind energy
- Renewable
- No pollutants
Name the disadvantages of wind energy
- cannot be stored
- can be unreliable and unpredictable
- Sound pollution and the blades can hit birds
the largest producer of energy in our solar system is the Sun !! We receive some of this energy through Solar energy, what is the main problem with solar energy
harnessing and transforming the energy of the sun is very difficult
The amount of solar radiation we receive is quite variable due to 4 main factors, name those factors
- the absorption and scattering of the solar rays when they hit small particles and molecules in our atmosphere
- air pollution, water vapour and clouds can block the sun’s rays from reaching the earth’s surface
- our location on earth in terms of lattitude (the closer we get to the equator, the more energy we receive)
- the season of the year and the time of day (we have more solar energy in the summer and during the daytime)
how does our lattitude on earth affect the amount of solar energy we can harvest
The closer we are to the equator means the sun’s rays hit us more directly, and therefor we receive more rays and therefor more energy!
during what season can we harvest more solar energy
during the summer
during what time of day can we harvest more solar energy
during the daytime
what is the goal of a panel of solar cells
it helps us transform solar energy into electrical energy
what are the steps through which a panel of solar cells help us transform solar energy into electrical energy
- the photovoltaic cells of the solar panel are made of silicon, a semiconductor
- this material can absorb photons of light
- when it absorbs the light, it releases an electron
- when the electron is released it generates electricity !
what are the advantages of solar energy
- renewable
- no pollutants
What are the disadvantages of solar energy
- costly
- limited by the amount of sun present
- not possible all day long
what is the main pre-requesite for tidal energy and is the reason why we cannot produce this energy anywhere in the world
a certain height is needed!!
Describe how the earth-moon system causes tides to appear
the gravitation force of the moon pulls water that is on the surface of the earth closest to it and creates a region of HIGH tide on that side and on the opposite side of the earth
this in turn creates regions of LOW tide on the sides of the planet that are not in the axis of the earth-moon system
Truth of False : in 24 hours, any given location on earth will experience 1 High tide and 2 low tides
FALSE, a location will have 2 high tides and 2 low tides in 24 hours
The moon creates high tides on earth due to its ____________ force
Gravitational
What is a spring tide
a spring tide is when the moon and the sun are aligned and therefor create an even higher tide on earth called the spring tide
What are the advantages of Tidal energy
- environment-friendly
- a highly predictable energy source
- operational and maintenance costs are low
- Renewable and inexhaustible source of energy
What are the disadvantages of Tidal energy
- negative influence on marine life forms
- only possible in a few locations (tide needs to be hugh)
- energy is only produces when there is a tide movement
the energy stored in the moving water in tidal energy is what form of energy
any motion is Kinetic Energy!
Describe the steps through which we can harvest tidal energy
- tide holds kinetic energy in the form of moving water
- we use this kinetic energy to spin a turbine and turn the energy into mechanical energy
- the turbine is attached to a generator which will also spin (mechanical energy)
- the spinning generator creates electrical energy !
