(p. 40)
REAL SACRIFICES
The faculty, upon occasion, of converting energy into matter
and matter into energy, constitutes one of the most wonderful
characteristics of chess, and reveals, perhaps, the innermost
secret of its fascination.
The question: "How can I favorably turn matter into
energy?" occurs as a rule in the early part of the game; the
converse is more likely to obtain for the later phase. We are
now concerned with the transformation of matter into energy
--the sacrifice of material for the sake of dynamic advantages.
Spielmann, Rudolf. 1995. The Art of Sacrifice in Chess. New York: Dover Publications, Inc.
They say c = 186,000 miles per second (whew !).
Is there a chart or equation where you can figure out the mass of an object if it's travelling, say, 185,000 mi/sec, then 185,500 mi/sec, etc. ? Knowing the particle has oo mass at 186,000 mi/sec.
Here's a calculator.
To answer your question, though, at 185,000 miles/second, the mass of an object is still only 8.5 times normal. You have to really get close to the speed of light before it takes off. At 186282 miles/second mass is 484 times normal, and at the 186282.39 miles/second it's 3648 times normal. At 186282.3969999, it is almost a million times the mass (186282.397 miles/second would be infinite mass).
Your statment is incorrect. Mass is a Lorentz relativistic invariant. This mean that mass is not dependent on the speed. What increase to infinity when a massive particle approches the speed of light is not its mass but its energy.