(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 10.6 kg weather rocket generates a thrust of 226.0 N. The rocket, pointing upward, is clamped to the top of a vertical spring. The bottom of the spring, whose spring constant is 402.0 N/m, is anchored to the ground. Initially, before the engne is ignited, the rocket sits at rest on top of the spring.

A: After the engine is ignited, what is the rocket's speed when the spring has stretched 19.4 cm past its natural length?

B: What would be the rocket's speed after travelling the distance if it weren't tied down to the spring?

2. Relevant equations

Es=0.5kx^2

Ek=0.5mv^2

Eg=mgy

3. The attempt at a solution

For A:

I tried making a conservation of energy equation:

Es=Ek+Eg

v=square root of ((kx^2 - 2mgy)/m)

That didn't work, since I don't know y (x=0.2584 m as per another part of the question). Do I need to take the thrust force into account?

I didn't even know where to start for B after getting stuck on A.

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# Homework Help: A rocket's speed

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