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Astrophysics/Logical Answer
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Question
While doing a physics problem dealing with the centripetal acceleration of a pulsar, I calculated the velocity of the pulsar by dividing the circumference of the pulsar by the amount of time it takes to make one rotation. My answer came out to be 2.85x10^(9)m/s. I know nothing can travel faster than the speed of light, but is this a logical answer.
Well, the minimum pulsar radius is about 10 km (circumference about 31 km) and the maximum pulse rate of a millisecond pulsar (MSP) is about 1000 Hz (debated, maximum reliable measurement is half that), giving us a maximum speed of about 31,000,000 m/s or about 10% of the speed of light. So no, not even close. Past that you start adding serious amounts of relativistic energy. And these are upper limits, so you're probably off by a factor of 100 somewhere.
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Steve Nelson
Expertise
Fusion, solar flares, cosmic rays, radiation in space, and stellar physics questions. Generally, nuclear-related astrophysics, but I can usually point you in the right direction if it's not nuclear-related or if it's nuclear but not astrophysics.
Experience
Currently a physics professor at the University of Texas of the Permian Basin. Doctoral dissertation was on a reaction in CNO-cycle fusion, worked in gamma-ray astronomy in the space science division of the naval research laboratory in the high-energy space environment branch.
Organizations
Physics professor at the University of Texas of the Permian Basin.
Education/Credentials
Ph.D. in physics, research was on nuclear fusion reactions important in stellar fusion.
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