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7. If the earth moves at a speed of 30 km per second, how long does it take the earth to move from one line of longitude to the next. Remember, there are 360 lines of longitude.

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group assessment: making deductions
1. We could make direct deductions. Yes No
2. We could give a sensible explanation for human survival. Yes No
3. We could formulate a rule about the distance of planets from the sun. Yes No
4. We could give a sensible explanation for the above. Yes No
5. We could calculate how long it takes the earth to move through one degree of longitude. Yes No
6. We could answer most of the questions independently. Yes No
7. Co-operation in the group was good. Yes No
8. Each individual made a contribution. Yes No

Group judges success of the exercise: ______________________________________

TASK 8

8.1 Mars – a rare planet

Read the facts below and discuss the questions in your groups.

  • Mars has a north and south pole that are white because of frozen snow and carbon dioxide.
  • The length of the day on Mars is only 41 minutes longer than the length of a day on Earth.
  • A year on Mars is however as long as 687 days on Earth. There are two seasons on Mars, summer and winter. During summer there are fierce dust storms, which make the sky appear pink and orange.
  • The dust absorbs energy from the sun and this allows the temperature to rise to 20 degrees Celsius.
  • The atmosphere on Mars is very thin and dangerous ultra-violet rays can thus reach the surface.
  • Scientists believe that long ago there was water on Mars with large rivers and seas. These days there is almost no water left on the surface but they suspect that there is underground water.
  • No photograph shows any sign of life on Mars. Life as we know it can only exist if there is oxygen.

QUESTIONS:

1. Why do scientists think that there was water on Mars long ago?

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2. If there was liquid water on Mars long ago, what can we deduce about the temperature on Mars at that time?

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3. Why is Mars so cold now?

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Questions & Answers

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.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
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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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