Halliday, Resnick & Walker — Rotation: Problem Problem_87

Pulsars. When a star with a mass at least ten times that of the Sun explodes outward in a supernova, its core can be collapsed into a pulsar, which is a spinning star that emits electromagnetic radiation (radio waves or light) in two tight beams in opposite directions. If a beam sweeps across Earth during the rotation, we can detect repeated pulses of the radiation, one per revolution. (a) The first pulsar was discovered by Jocelyn Bell Burnell and Antony Hewish in 1967; its pulses are separated by 1.3373 s. What is its angular speed in revolutions per second? (b) To date, the fastest spinning pulsar has an angular speed of 716 rev/s. What is the separation of its detected pulses in milliseconds?