Rocket Propulsion Homework: Calculating Mass Loss R

AI Thread Summary
To calculate the average mass loss R during burnout for the Roadrunner F45 rocket engine, the thrust curve must be analyzed to determine the average thrust (Ma). However, the challenge lies in calculating the relative velocity (Vrel), which is necessary for using the formula R = Ma/Vrel. The discussion highlights that without Vrel, finding R is problematic, and some participants are exploring alternative methods to derive R. Additionally, impulse calculations have been attempted, but they do not directly resolve the issue of determining R without Vrel. The conversation emphasizes the need for a clear method to calculate Vrel to proceed with finding R.
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Homework Statement



A Roadrunner F45 rocket engine, of mass 93g, is attached to a 2kg cylinder, which glides along a horizontal low friction nylon fishing wire. The thrust curve for the rocket engine is given.

In reality, 30g of propellant are burned as the engine is ignited. Calculate the average of mass loss R during burnout, in kg/s


Homework Equations



R= Ma/Vrel

The Attempt at a Solution



I guess Ma is the average thrust which I could calculate by using the graph. However, I don't know how to calculate V rel ( which is actually the next part of the problem). Is there any way I can calculate R other than use the normal formula ??

I have also calculated the impulse for the rocket.
 
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Anyone found out about anything yet ??

I have been trying but still cannot find R without calculating Vrel
 

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Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
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