How Do You Calculate the Thrust of a Rocket at Takeoff?

Thread starter kmax12
Start date Oct 21, 2007

AI Thread Summary

To calculate the thrust of a rocket at takeoff, multiply the mass flow rate of the propelling gases (1200 kg/s) by their exit velocity (39700 m/s), resulting in a thrust of 47,640,000 N. Gravity does not need to be factored into this specific thrust calculation, as thrust is determined by the momentum change of the expelled gases according to Newton's third law. The conservation of energy principle is relevant but not necessary for this basic thrust calculation. The calculated thrust value represents the force exerted by the rocket at takeoff. This method effectively demonstrates how thrust is derived from the mass flow and velocity of expelled gases.

Oct 21, 2007

kmax12

Calculate the force exerted on a rocket, given that the propelling gases are expelled at a rate of 1200 kg/s with a speed of 39700 m/s (at the moment of takeoff).

DO i just multiply? do i have to take gravity into consideration?

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Oct 21, 2007

MrXow

Use conservation of energy along with Newton's third law.

Oct 21, 2007

kmax12

so i muliply 1200 and 39700 to get the reaction force , that equals 47,640,000. Is that my answer

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