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Homework Help: Momentum Physics Question

  1. Oct 1, 2011 #1
    Far in space, where gravity is negligible, a 495kg rocket traveling at 85.0m/s in the positive x-direction fires its engines. The figure shows the thrust force as a function of time. The mass lost by the rocket during these 30.0s is negligible.

    The variation of F vs t chart is described as t on the x axis and goes fron 0 to 30s, on the y axis it goes up to 1000N and the graph goes from 0N at 0s up to 1000N at 10s then back down to 0N at 30 seconds.

    1. What impulse does the engine impart to the rocket? in N*s

    2. What is the maximum speed?
  2. jcsd
  3. Oct 1, 2011 #2


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    Homework Helper

    The area under Force - time graph gives the impulse. Impulse gives the change in momentum. the change in momentum will give you the change in velocity.

    If the force changes direction - or is in a direction different to the initial velocity you have to involve trigonometry / Pythagorus
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