Calculate Rocket Momentum & Thrust: 20,000kg, 600kg/s, 300m/s

Thread starter Spakfilla
Start date Dec 17, 2010
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Calculations Rocket

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To calculate the momentum of the exhaust gases from a 20,000kg rocket expelling gases at 600kg/s with a velocity of 300m/s, the momentum (p) is determined using the formula p=mv, resulting in a momentum of 180,000 kg·m/s. The thrust (F) applied to the rocket engines can be deduced using the formula F=ma, where the acceleration (a) is derived from the change in velocity over time. Given that the mass flow rate is 600kg/s and the exhaust velocity is 300m/s, the thrust is calculated to be 180,000 N. These calculations illustrate the fundamental principles of rocket propulsion and momentum transfer. Understanding these concepts is crucial for analyzing rocket performance and design.

Dec 17, 2010

Spakfilla

A 20 000kg rocket exhausts gases at a constant 600kg per second at 300ms^-1

a) Calculate the momentum of the exhaust gases

b) Deduce the thrust applied to the rocket engines

Any help would be much appreciated

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Dec 17, 2010

Rick88

Just use:

p=mv

and a=dv/dt

(and F=ma, of course).

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