Recent content by jeanmarc69

  1. J

    Undergrad Car, gas and total energy calculation

    Hi, What I understood about the principle of conservation of energy: Et = Ep + Ec = constant. For example: Et = 1/2mv^2 + mgh (h = height). Consider a car moving at speed v. For example: Et = 1/2mv^2 + E(gas + exhausts). Indeed, I include the exhausts, otherwise with the drop in the quantity...
    • jeanmarc69
    • Thread
    • Conservation of energy Total energy
    • Replies: 3
    • Forum: Mechanics
  2. J

    High School Void between Plank particle and Quark.... what else?

    Yes indeed a lot of things on Internet... Thank you for your replies !
  3. J

    High School Void between Plank particle and Quark.... what else?

    Thank for your reply FYI, my question was based on this YouTube film:"Size comparison of the universe 2016". Actually what stroke me are those gaps between the different objects in the micro world. For me the question is: Can the universe produce an infinite number of sizes from the...
  4. J

    High School Void between Plank particle and Quark.... what else?

    Hi- Between the Planck particle and the Quark, these is a sizeable relative difference of about 10^15, or in other words and size unit, as if there were no objet whose size would stand between ours (about 1.70 m) and Antares... this is not only about vacuum (or void) in absolute term but also...