physics
posted by sonia .
i need help figuring out what formaula to use for finding the final velocity of a rocket.
Model rocket engines are sized by thrust, thrust duration, and total impulse, among other characteristics. A size C5 model rocket engine has an average thrust of 5.26 N, a fuel mass of 12.7 g, and an initial mass of 25.5 g. The duration of its burn is 1.90 s.
If this engine is placed in a rocket body of mass 57.5 g, and if the rocket is fired in outer space, what is the final velocity of the rocket? Assume the fuel burns at a constant rate.

You need to derive or find the "rocket" formula for the velocity of an object that has a fixed force T applied while its mass is decreasing. Calculus is needed to derive it.
You can find it at
http://www.ebtx.com/mars/rocketeq.htm
You will need the rocket exhaust velocity, Ve.
You can get if from
T = dm/dt * Ve
where dm/dt is the rate of mass release, 12.7*10^3 kg/1.90 s,
and T is the thrust in Newtons
Respond to this Question
Similar Questions

physics
if a rocket engine delivers a constant thrust, does it deliver more power as the rocket speeds up force = mass*(acceleration) if the rocket accelerates, the force will increase wow,uh constant thrust means it is delivering constant … 
physics
Model rocket engines are sized by thrust, thrust duration, and total impulse, among other characteristics. A size C5 model rocket engine has an average thrust of 5.26 N, a fuel mass of 12.7 g, and an initial mass of 25.5 g. The duration … 
science
The engines of a 1.20 x 10^5 N rocket exert an upward thrust of 2.00 x 10^5 N for 1.50 minutes upon lift off. What is the impulse exerted on the rocket? 
physics
The engines of a 1.20 x 10^5 N rocket exert an upward thrust of 2.00 x 10^5 N for 1.50 minutes upon lift off. What is the impulse exerted on the rocket? 
Physics
A typical model rocket has a mass of 50 g. Similarly, a typical "class C" model rocket engine can produce a total impulse of 10 Newtonseconds. We usually launch model rockets vertically, but if I instead launched this rocket horizontally, … 
PHYSICS
Model rockets are lightweight rockets powered by very small engines. A typical model rocket has a mass of 5g.Similarly, a typical "class C" model rocket engine can produce a total impulse of 10 Newtonseconds. We usually launch model … 
motion,physics
Model rockets are lightweight rockets powered by very small engines. A typical model rocket has a mass of 5g.Similarly, a typical "class C" model rocket engine can produce a total impulse of 10 Newtonseconds. We usually launch model … 
physicsforces
1. a fully loaded rocket has a mass of 2.92x10^6kg. It's engines has a thrust of 3.34x10^7N a)what is the downward force of gravity of the rocket at blast off? 
Physics
A 360 g model rocket is on a cart that is rolling to the right at a speed of 2.5 m/s. The rocket engine, when it is fired, exerts an 8.5 N thrust on the rocket. Your goal is to have the rocket pass through a small horizontal hoop that … 
Physics
A model rocket has a mass of 0.435 kg. It is mounted vertically and launches directly up with a thrust force of 13.1 N. a) What is the weight of the rocket?