• audiomodder@lemmy.blahaj.zone
    50·
    5 months ago

    It seems weird to me that they would measure a thruster in maximum speed and not by the force is generates. Doesn’t the maximum speed depend on the mass it is propelling and a bunch of other factors like friction and gravity?

    • PflaumeKordel@feddit.de
      14·
      5 months ago

      This speed is the Specific Impulse which is a measure of how effective the fuel mass is used. It is equivalent to the effective exhaust velocity, which is basically the mean exhaust velocity as the real exhaust velocity depends on the position in the exhaust. The specific impulse is more often given in seconds like in the Wikipedia page for the thruster and this representation is connected to the speed-based representation by dividing the effective exhaust velocity by the standard gravitational acceleration at sea level. Mass is not present in both of these representations because this way they are the impulse per unit mass of propellant.

      Electric thrusters reach very high exhaust velocities, but the fuel mass flow is limited which leads to low thrust. Chemical engines reach high thrust, but their exhaust velocities are quite low in comparison.

    • MonkderDritte@feddit.de
      106·
      5 months ago

      No, that is the time to maximum speed. Maximum speed depends solely on exhaust speed (how fast the particles get accelerated).

      And no friction in space. Well, almost none.

      What’s weird is that they say km/h. Space and rocket stuff is usually in m/s.

      • wisha@lemmy.ml
        172·
        5 months ago

        The grandparent comment is correct. There is no such thing as engine-specific “maximum speed”. If you add more fuel, you can always go faster (until the speed of light).

        • NoSpotOfGround@lemmy.world
          3·
          5 months ago

          Even “until the speed of light” has a caveat (hear me out). Would you call getting from A to B in 1 hour on your watch instead of 2 as “faster”? If your answer is yes, then there’s no limit to how “fast” you can go. You could get from here to the Andromeda Galaxy in one minute. It’s just that for the Andromeda and the Milky Way a LOT more time would have passed.

      • Eheran@lemmy.world
        3·
        5 months ago

        You are incorrect. If I am traveling at 90 % speed of light, take a stone and throw it out the back… I am now faster.

  • clearedtoland@lemmy.worldEnglish
    82·
    5 months ago

    I was going to joke and say: that’s like, what, warp 0.0001.

    In the Star Trek universe, warp factors are a way to measure faster-than-light travel. The speed of light is approximately 299,792 kilometers per second (km/s). To convert your given speed of 32,000 km/hr into a warp factor, we need to use the formula that relates warp factor to the speed of light:

    v = c * (w^(10/3))

    where:

    •	v is the speed in multiples of the speed of light (c),
•	w is the warp factor.

    First, convert 32,000 km/hr into kilometers per second (km/s):

    32,000 km/hr = 32,000 / 3,600 km/s ≈ 8.89 km/s

    Now, find the warp factor using the speed of light:

    w = (v / c)^(1 / (10/3))

    w = (8.89 km/s / 299,792 km/s)^(1 / (10/3))

    Calculate the fraction inside the parentheses:

    8.89 / 299,792 ≈ 0.00002967

    Now raise this to the power of 3/10:

    0.00002967^(3/10) ≈ 0.000657

    So, approximately:

    w ≈ 0.000657

    Therefore, a speed of 32,000 km/hr corresponds to a very low warp factor, approximately Warp 0.000657 in the Star Trek scale.