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Acceleration of Space Shuttle at Lift Off

1. The problem statement, all variables and given/known data

The mass of a space shuttle is approximately 2.0 x10^6 kg. If the thrust provides a force of 1.2 x 10^7 N, what is the acceleration of the space shuttle at lift off?
6.0 m/s2
0.06 m/s2
1.67 m/s2
0.167 m/s2

2. Relevant equations
Resultant force = thrust – weight
Acceleration = resultant force ÷ mass


3. The attempt at a solution
Weight: 2.0 x10^6 kg*9.8=19600000
Resultant Force: 1.2 x 10^7 N-19600000=-7600000
Acceleration: -7600000/2.0 x10^6 kg= -3.8 m/s^2
Not a choice and a negative acceleration
 
Last edited:

berkeman

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1. The problem statement, all variables and given/known data

The mass of a space shuttle is approximately 2.0 x10^6 kg. If the thrust provides a force of 1.2 x 10^7 N, what is the acceleration of the space shuttle at lift off?
6.0 m/s2
0.06 m/s2
1.67 m/s2
0.167 m/s2

2. Relevant equations
Resultant force = thrust – weight
Acceleration = resultant force ÷ mass


3. The attempt at a solution
Getting a negative acceleration.
Welcome to the PF.

Please show your work in detail so we can look for mistakes... :smile:
 

SteamKing

Staff Emeritus
Science Advisor
Homework Helper
12,794
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1. The problem statement, all variables and given/known data

The mass of a space shuttle is approximately 2.0 x10^6 kg. If the thrust provides a force of 1.2 x 10^7 N, what is the acceleration of the space shuttle at lift off?
6.0 m/s2
0.06 m/s2
1.67 m/s2
0.167 m/s2

2. Relevant equations
Resultant force = thrust – weight
Acceleration = resultant force ÷ mass


3. The attempt at a solution
Getting a negative acceleration.
That's because you were given incorrect data for the total thrust at take off.

https://en.wikipedia.org/wiki/Space_Shuttle

The Shuttle used 3 SSME (Space Shuttle Main Engines) which provide a total thrust of 5250 kN at sea level. In addition to these, there were two Solid Rocket Boosters (SRB) which provided a thrust of 12,500 kN each.
 
That's because you were given incorrect data for the total thrust at take off.

https://en.wikipedia.org/wiki/Space_Shuttle

The Shuttle used 3 SSME (Space Shuttle Main Engines) which provide a total thrust of 5250 kN at sea level. In addition to these, there were two Solid Rocket Boosters (SRB) which provided a thrust of 12,500 kN each.
That would be a total thrust of 30,250,000 N. Then you'd do 30,250,000N-19,600,000= 10,650,000 to get resultant force.
The resultant force/mass would be: 10,650,000/2.0 x10^6 kg= 5.3 m/s^2. Right?? And that's not an answer choice.
 

SteamKing

Staff Emeritus
Science Advisor
Homework Helper
12,794
1,662
That would be a total thrust of 30,250,000 N. Then you'd do 30,250,000N-19,600,000= 10,650,000 to get resultant force.
The resultant force/mass would be: 10,650,000/2.0 x10^6 kg= 5.3 m/s^2. Right?? And that's not an answer choice.
There's only one correct answer. There are infinitely many incorrect answers. :frown:

I think whoever wrote this question wanted you to just divide the thrust value given in the problem by the mass of the shuttle to obtain an answer. It's just that this is one of the infinitely many incorrect answers.
 

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