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Natural sciences

Planet earth and the universe

The inner planets

Educator section


Assignment 5:

1. Mercury

2. There is no oxygen and no water on Mars. The atmosphere is also too thin to keep out harmful UV rays.

3. Venus has almost the same mass and size as the earth.

4. Venus (sulphuric acid)

5. The orbit of Mars is much closer to the Sun than Neptune’s.

6. The Moon.

7. There is iron in the ground that gives it the red colour.

8. Sufficient oxygen and water; climate is suitable for vegetation, atmosphere correct depth and density.

9. If emergency signals are sent they reach the earth only two hours later. Sometimes the reception is very bad.

Total: 10

Assignment 6:

  • Use assessment matrix

Assignment 7:

1. Venus and the Moon.

2. 150 million km. This is the distance that the Earth is from the Sun and where we currently survive.

3. Mercury.

4. Venus and Mars lie on either side of the Earth, not too near or too far from the Sun.

5. Yes. The nearer the planet to the Sun, the higher the average speed.

6. Possible as a result of the gravity and energy of the Sun.

Four minutes.24 x 60 minutes = 1440 minutes (it takes the earth 24 hours to rotate on its own axis)1400 minutes divided by 360 degrees = 4 minutes.

Assignment 8.1:


1. Photographs show that there are dry river beds on Mars. All the water has frozen and is collected at the poles. We surmise that there were large seas and rivers. This water is now underground.

2. The average temperature is possibly higher.

3. Mars is further from the Sun and thus receives less energy from the Sun. Although the Sun is a huge source of energy it will one day shrink and weaken.

4. One would breathe with difficulty and take shallow breathes. One would die quickly as there is too much carbon dioxide in the air.

Assignment 8.2:


1. -60 degrees

2. Day 1 18:20

Day 2 10:45

3. Day 1 14:30

- 15 degrees

4. from 06:00

5. When there is a dust storm it absorbs heat from the Sun which causes the temperature to rise. There is also carbon dioxide in the Martian atmosphere and this can also raise the temperature.

  • Open answer; any realistic explanation.

Leaner section


Activity: to discuss the planets of our solar system [lo 1.2, lo 1.3, lo 2.1, lo 2.2, lo 2.3]

  • Mercury

This is the closet planet to the sun. Mercury has many craters on its surface caused by asteroids which have collided with the planet. Mercury has no atmosphere or any moons. The temperature at the equator is approximately 400 degrees Celsius and at the poles it is –150 degrees Celsius.

  • Venus

Venus has an atmosphere of carbon dioxide that is much thicker than the earth’s atmosphere. The surface is hidden beneath thick clouds of sulphuric acid. Temperatures at the surface reach approximately 480 degrees Celsius. Venus is about the same size as the earth and has about the same mass.

  • Earth

As far as we know the earth is the only place in the universe where life occurs. Temperatures on the surface vary between 60 degrees and –90 degrees Celsius. Approximately two thirds of the surface is covered by liquid water.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Natural sciences grade 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11077/1.1
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