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Suppose a body is at rest of mass m. If the same body is accelerated at velocity v, the mass increases to some definite amount. Since the mass of the body has increased, will the gravitational field of the body change in proportion to the increase in mass?

Sykhow
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    "The concept of "relativistic mass" is subject to misunderstanding. That's why we don't use it. First, it applies the name mass – belonging to the magnitude of a 4-vector – to a very different concept, the time component of a 4-vector. Second, it makes increase of energy of an object with velocity or momentum appear to be connected with some change in internal structure of the object. In reality, the increase of energy with velocity originates not in the object but in the geometric properties of spacetime itself." 'Relativistic mass' isn't really used anymore – Gert Sep 16 '19 at 13:49
  • See https://en.wikipedia.org/wiki/Mass_in_special_relativity#Controversy – Gert Sep 16 '19 at 13:50
  • Also see https://physics.stackexchange.com/q/133376/123208 – PM 2Ring Sep 16 '19 at 13:55
  • You might find the following link helpful: How do I ask a good question? - "Have you thoroughly searched for an answer* before asking your question? Sharing your research helps everyone. Tell us what you found and why it didn’t meet your needs. This demonstrates that you’ve taken the time to try to help yourself, it saves us from reiterating obvious answers, and above all, it helps you get a more specific and relevant answer!"* – Alfred Centauri Sep 16 '19 at 14:18

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When you accelerate a chunk of mass to some velocity, you are increasing its energy content. Since energy can bend spacetime like mass does, a more energetic chunk of mass will bend spacetime (that is, exert gravitational pull) a bit more strongly than a less energetic chunk of mass.

Explicitly separating out mass effects from energy effects (which is the way the subject is currently taught) lets physics people keep track of the basic physics in a less-complicated way than how they would if they thought of the speedy object's "intrinsic" mass as having been increased because of its velocity- which is how this subject used to be taught 50 years ago.

As long as you keep proper account of the physics, either way of thinking about the subject will yield the same (correct) solution to a problem, but the modern approach- which asserts that the intrinsic mass of an object is invariant- is the currently accepted formalism.

niels nielsen
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