Relativistic Energy and Momentum: Part A: A meteorite of mass 1500kg moves with
ID: 1377513 • Letter: R
Question
Relativistic Energy and Momentum:
Part A: A meteorite of mass 1500kg moves with a speed of 0.700c . Find the magnitude of its momentum p.
Part B: Compare your answer to Part A with what you would have found had you used the classical expression for momentum p=mv. How do the relativistic and the classical momenta compare?
Part C: What is the total energy E of the meteorite?
Part D: What would the energy of the meteorite be if it were at rest?
Part E: What is the relativistic kinetic energy K of the meteorite when it travels at 0.700c ?
Part F: Compare your answer to Part E with what you would have found if you had used the classical expression for kinetic energy: K=12mv2. How do the relativistic and classical expressions for kinetic energy compare?
HERE'S THE ANSWER!!!!
Explanation / Answer
Solution: Part A: According to the special theory of relativity,
Momentum p = mv = m0v/(1-v2/c2)1/2 where symbols have their usual meaning.
Calculating, p = 4.41 x 1011 kg-m/s.
Part B: considering classical p = mv, the momentum becomes p = 3.15 x 1011 kg-m/s.
Relativistic momentum is more compared to the classical momentum.
Part C: Relativistic total energy can be expressed as E = m0c2/(1-v2/c2)1/2, with symbols having their usual meaning. So, E = 1.89 x 1020 J.
Part D: if the meteorite be at rest, its energy will be E = m0c2 = 1.35 x 1020 J.
Part E: Relativistic energy can be expressed as E2 = m02c4 + p2c2, with symbols having their usual meaning. So, E = 2.71 x 1040 J.
Part F: Considering classical formula, kinetic energy will turn out to be Ek = 3.3 x 1019 J.
Evidently, relativistic kinetic energy is much more colossal than the classical counterpart.