Finding the fuel that ISS is using to change its orbit

[Ramulala]

Hello guys,
I am stuck on a physics question. Although I know the procedure to solve it but I am not good at calculating numbers. I mess up a lot when I am calculating.

Calculate how much fuel was used when ISS ( international space station) corrects its orbits. The fuel flows at 0.32(kg/s) through the progress engines when the process starts. The re- boost of orbit applies a Delta V of precisely 24.6942 (m/s). The space station's mass is 246733kg. The combined thrust of engines is 821.3 Newtons of force. Answer must be in (kgs)

Procedure of what I did:

First calculate acceleration using F= M•A - which is dividing the 821.3N/ 246733 kg = getting answer in m/s squared
Then dividing the Delta V to the Acceleration that we found above to get the engine burn time.
Then divide it by the fuel flow rate of 0.32 (kg/s) to get how much fuel will be used.

 

[HallsofIvy]

So you are having difficulty with the arithmetic? Aren't you using a calculator?

 

[Deleted member 4993]

Hello guys,
I am stuck on a physics question. Although I know the procedure to solve it but I am not good at calculating numbers. I mess up a lot when I am calculating.

Calculate how much fuel was used when ISS ( international space station) corrects its orbits. The fuel flows at 0.32(kg/s) through the progress engines when the process starts. The re- boost of orbit applies a Delta V of precisely 24.6942 (m/s). The space station's mass is 246733kg. The combined thrust of engines is 821.3 Newtons of force. Answer must be in (kgs)

Procedure of what I did:

First calculate acceleration using F= M•A - which is dividing the 821.3N/ 246733 kg = getting answer in m/s squared
Then dividing the Delta V to the Acceleration that we found above to get the engine burn time.
Then divide it by the fuel flow rate of 0.32 (kg/s) to get how much fuel will be used.

First calculate acceleration using F= M•A - which is dividing the 821.3N/ 246733 kg = getting answer in m/s squared
Then dividing the Delta V to the Acceleration that we found above to get the engine burn time.
Then divide it by the fuel flow rate of 0.32 (kg/s) to get how much fuel will be used

You said:

Procedure of what I did:

Does that mean you have followed the "said" procedure?

If "yes", then instead of saying it in words - please show the numerical steps and associated result.

 

[Ramulala]

F= M/A -- 821.3n/246733kg = .0033286994

Now dividing it by delta V 24.6942 m/s / .0033286994 = 7418.573152 of burn time

Now dividing 7418.573152 by 0.32 kg/s gives me = 23,183 as a answer of fuel.

I need a answer in kgs, I not sure on if it did all the conversions right. You know like from kg to m/s) etc. If anyone could follow my procedure to check if I did those right would be very helpful!!!

 

[Deleted member 4993]

F= M/A -- 821.3n/246733kg = .0033286994 ← unit of force in SI is N (= kg * m/s²)

How did you get this equation?......................Now dividing it by delta V 24.6942 m/s / .0033286994 = 7418.573152 of burn time

Now dividing 7418.573152 by 0.32 kg/s gives me = 23,183 as a answer of fuel.

I need a answer in kgs, I not sure on if it did all the conversions right. You know like from kg to m/s) etc. If anyone could follow my procedure to check if I did those right would be very helpful!!!

 

[Ramulala]

I know it is confusing. The equation for Delta V is already given to me. I am confused on how to solve a problem like this-- 24.6942 (m/s) then divided by the .0033286994 (kg* m/s^2)--- so by doing it like how will you convert s^2 or eliminate it get the proper dimensions on it. Like the one you just posted **(= kg * m/s2)**

Will it be -- 7418.573152 (kg* m/s) with no squared or just (kg* s)

I am sorry if this is confusing, I have taken a online course that requires to do these problems about space and physics. I guess you have to have a prior knowledge to solve these.

 

[Deleted member 4993]

I know it is confusing. The equation for Delta V is already given to me. I am confused on how to solve a problem like this-- 24.6942 (m/s) then divided by the .0033286994 (kg* m/s^2)--- so by doing it like how will you convert s^2 or eliminate it get the proper dimensions on it. Like the one you just posted **(= kg * m/s2)**

Will it be -- 7418.573152 (kg* m/s) with no squared or just (kg* s)

I am sorry if this is confusing, I have taken a online course that requires to do these problems about space and physics. I guess you have to have a prior knowledge to solve these.

Did they give you a FORMULA for "burn time"?

What is it?

 

[Ramulala]

Here is the exact question! Take a look!