4 ms·
A spinning top weighs more than a top at rest? I get that mass increases with speed, but that works in a rotating system as well as a linear system?
by EthanHeilman 6y ago
A spinning top weighs more than a top at rest? I get that mass increases with speed, but that works in a rotating system as well as a linear system?
- skzv 6y agoAt any given instant, velocity is linear. That is, if you take a snapshot of the top, you can draw a straight vector for each particle of the top, indicating the direction of velocity. And, if the top suddenly flew apart, each piece would continue in a straight line, following its velocity at that instant.
- EthanHeilman 6y agoCan velocity exist in a snapshot?
- skzv 6y agoOr rephrased: is instantaneous velocity real? Are limits real, or just a mathematical invention? Well, I think instantaneous velocity is real, and I think I have a convincing argument. Imagine you have a piece of gum stuck to your bike tire. As your tire spins, the piece of gum spins with it, and its velocity is constantly changing. But when the piece of gum flies off your tire, it flies off in a straight line, following the instantaneous velocity at the moment of separation. Seeing as the gum can fly off in a straight line, its instantaneous velocity at that moment must be well-defined.
- selimthegrim 6y agoRelativistic mass is not a well defined abstraction.
- Ma8ee 6y agoBoth phenomena are a consequence of the equivalence between mass and energy. So since a spinning top has a higher energy than one at rest, it will also have a higher mass. Another example is that an excited atom has a higher mass than the same atom in its ground state.