posted by Alexandra on .
A 10.2 kg weather rocket generates a thrust of 200N. The rocket, pointing upward, is clamped to the top of a vertical spring. The bottom of the spring, whose spring constant is 500N/m, is anchored to the ground.
a) Initially before the engine is ignited, the rocket sits at rest on top of the spring. How much is the spring being compressed?
ANSWER. 0.2m or 20 cm
b) After the engine is ignited, what is the rocket's speed when the spring has stretched 40 cm? For comparison, what would the rocket's speed be after traveling this distance if it weren't attached to the spring?
Help with B please!!!
Why would anyone attach a rocket to a spring?
I suggest using conservation of energy for this problem. Power delivered to Rocket = (Thrust)*(distance travelled, X)
After you subtract the spring potential energy (1/2)kX^2 , the remainder is the kinetic energy of the rocket.