Recent content by lilshai

  1. L

    Does a Warm Gasoline and Air Mixture Rise in a Cooler Environment?

    Hello, I have a question about the following statement: "It is well known that warm air in a cooler environment rises. Now consider a warm mixture of air and gasoline on top of an open gasoline can. Do you think this gas mixture will rise in a cooler environment?" I would say Yes, the...
  2. L

    What Is the Maximum Height and Time for a Rocket with Initial Thrust?

    "Your mistake is assuming the vehicle reaches maximum height when the rocket stops thrusting." How come? After the engine stops, the rocket would fall back down rite...so wouldn't the max height be when v = 0, or when the thrust terminates?
  3. L

    What Is the Maximum Height and Time for a Rocket with Initial Thrust?

    Yes, do I need to convert the thrust to Newtons? 1 lb = 4.448 N m = W/g = 0.2 lb/32.2 ft/sec^2 a = (F[SIZE="1"]t-mg)/m = [(2 lb - 0.006211 (lb*sec^2/ft)(32.2 ft/sec^2)]/[0.006211 lb*s^2/ft] v0 = 0 y-y0=v0t+1/2(at)^2 y-y0 = 1/2(289.8 ft/sec^2)(1 sec)^2 y-y0 = 144.9 ft
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    What Is the Maximum Height and Time for a Rocket with Initial Thrust?

    Homework Statement A 0.2-lb model rocket is launched vertically from rest at time t=0 with a constant thrust of 2 lb for one second and no thrust for t > 1 sec. Neglecting air resistance and the decrease in mass of the rocket, determine (a) the maximum height h reached by the rocket, (b) the...
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