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-   -   Outer Space 10^3 to 10^9 (http://www.physicsforums.com/showthread.php?t=330095)

ania 5555 Aug11-09 08:37 AM

Outer Space 10^3 to 10^9
 
Please can you help me with these question;

1)Which bonds can be broken by UV radiation in space?

I've done it but I'm not sure if this is correct.
Covalent bond can be broken by UV radiation in space such as; O-O, N-N, C-N, C-C,
C-O, and double pi bond C=C

2)Consider an area (A) of Kapton that is 1cm2. Assume (i) that the flux of AOs (F) is 2.5 x 1020 atoms/cm2/s and (ii) that 3.04 x 10-24 cm3 Kapton is removed per AO (RE: reaction efficiency). Then the rate of loss of film thickness (x) (- dx/dt=A x F x RE) is (3.5x1020 AO/cm2/s) x (3.04 x 10-24 cm3/ AO). What is the rate of Kapton film loss in space? If the film is 1cm thick, how long will it last attack by AOs if the rate remains constant?????
AO- atomic oxygen

3)If the rate of adsorption (dθ/dt) is kax p02 x (1-θ) exp (-Ea/RT) what is the time for a 1m2 window to be covered by O2 at an altitude of 300km above the Earth’s surface?

4)Suggest one object that would be better produced in space than on Earth??

Redbelly98 Aug12-09 08:06 AM

Re: Outer Space 10^3 to 10^9
 
Welcome to PF :smile:

You'll have to show an attempt at solving HW problems before receiving help (forum policy).

Also, it's better to make a separate thread for each question. If we had a running discussion involving 4 separate problems in one thread, it could get pretty confusing as to who is talking about which problem.

ania 5555 Aug14-09 05:46 AM

Re: Outer Space
 
1) If the rate of adsorption (dθ/dt) is kax p02 x (1-θ) exp (-Ea/RT) what is the time for a 1m2 window to be covered by O2 at an altitude of 300km above the Earth’s surface?

Redbelly98 Aug14-09 08:58 AM

Re: Outer Space 10^3 to 10^9
 
Thanks for limiting it to a single question. You'll still have to show your attempt at a solution before receiving help (forum policy).

For more details, scroll down to the Homework Help section here:
http://www.physicsforums.com/showthread.php?t=5374

tom jones Aug15-09 12:20 PM

Re: Outer Space 10^3 to 10^9
 
surrey physical haha


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