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Dot Point Physics Help Please (1 Viewer)

clissold

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Heeeeeey Everyone :spin:

If you could answer any or all of the following questions, that would be much appreciated.


3.4.2

Calculate how far an astronaut would need to be away above the Earth in order for his weight to be 0.01 his weight on the Earths surface.


3.4.3

a) An astronaut is in a satellite orbiting the Earth at an altitiude of one Earth radius. What is the gravitational force acting on him compared to his weight on the surface of the Earth? Justify your answer.

b) The satellite is boosted to double this altitude. What is the new gravitational force acting on the astronaut?

c) Calculate the orbital velocity of the astronaut in this higher orbit.


4.22

Discuss the implications of mass increase, time dilation, and length contraction for space travel.


Thankyou..!!
 

FCB

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I wish i knew how to use latex like exploitable. Anyways here are my answers. If they are wrong let me know...

Ill take mass of Earth to be 5.974x10^24
g=GM/r^2
0.098=((6.67x10^-11)x(5.974x10^24))/r^2

Now make r^2 the subject and you then get an answer of something 4.066x10^15 and thus r=(4.066x10^15)^0.5 which is 63765018m

Then you minus the earths radius which is 6378000 and your answer should be something like 63765018m
 

hscishard

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Heeeeeey Everyone :spin:

If you could answer any or all of the following questions, that would be much appreciated.


3.4.2

Calculate how far an astronaut would need to be away above the Earth in order for his weight to be 0.01 his weight on the Earths surface.


3.4.3

a) An astronaut is in a satellite orbiting the Earth at an altitiude of one Earth radius. What is the gravitational force acting on him compared to his weight on the surface of the Earth? Justify your answer.

b) The satellite is boosted to double this altitude. What is the new gravitational force acting on the astronaut?

c) Calculate the orbital velocity of the astronaut in this higher orbit.


4.22

Discuss the implications of mass increase, time dilation, and length contraction for space travel.


Thankyou..!!
a) 1/4. Sub 2r into the formula.
b) 1/16. [2(2r)]^2 = 16
c) Use kepler to find T. Then use 2pir/T
 

FCB

Emma Watson <3
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Heeeeeey Everyone :spin:

If you could answer any or all of the following questions, that would be much appreciated.


3.4.2

Calculate how far an astronaut would need to be away above the Earth in order for his weight to be 0.01 his weight on the Earths surface.


3.4.3

a) An astronaut is in a satellite orbiting the Earth at an altitiude of one Earth radius. What is the gravitational force acting on him compared to his weight on the surface of the Earth? Justify your answer.

b) The satellite is boosted to double this altitude. What is the new gravitational force acting on the astronaut?

c) Calculate the orbital velocity of the astronaut in this higher orbit.


4.22

Discuss the implications of mass increase, time dilation, and length contraction for space travel.


Thankyou..!!
1) Okay if you remember that gravitational force is directly proportional to the masses and inversly proportional to the square of the distance then you should be safe
Just use g=GM/r^2 and sub in values and set the radius as 12756000 as that is 2 times the radius of earth as stated in the question. The answer you should obtain is 2.448849ms^-2

2)Take the answer above of 2.448849 and divide by 4. Or you can get 9.8 and divide by 16, Its your choice

3)(GM/r)^1/2
((6.67x10^-11)(5.974x10^24))/(25512000)^1/2
Answer should be like 3952ms^-1

4)Get to places faster within life time and stuff like that. I wish i could help you but its alot of information and best for you to approach notes or text book.
 

FCB

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I think i may have mucked number 3 up by substituting in 4 times Earths Radius instead of 5

I think the answer should be 3534ms^-1



Someone please correct me if im wrong.
 

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