How do I Calculate Average Thrust when given t, v, delta m

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BigREDgrin
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Homework Statement


During a .0050 second time period a rocket expels 1.000kg of gas at a velocity of 5000 m/s. Calculate the rockets average Thrust, as well as Impulse. http://imgur.com/a/uE9dVI am going to use this note for reference on a test and want to rock solid about it.

2. Homework Equations

I have the formulas given by my professor are

Thrust= v exhaust * (delta mass / time)

Impulse rocket= v exhasut (delta mass)= delta p rocket

The Attempt at a Solution


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Like I said I want to be sure of this so I can refer to it later. Here is my best try

Thrust= (5000m/s)*(1.000kg/.0050s) = 5000 m/s * 200 kg/s= 10000000 kg m/s

Impulse= 5000 m/s (1.000 kg) = 5000kg m/s

So please tell me if and where I have gone wrong.
 
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Looks good from where I'm at.
 
Thanks for your response. I am in the process of doing the same with Coefficient of Restitution, speed of approach over speed of separation. Thanks again
 
BigREDgrin said:
10000000 kg m/s
Check the number of zeroes.
The way the information is stated makes me suspect they are also looking for the right precision being expressed in the answer. It might be better to write it as 1.000 (or whatever is the right precision) times a power of ten.