Answer:
Speed,
![v=1.25* 10^5\ m/s](https://img.qammunity.org/2021/formulas/physics/high-school/geiwg55vhbxzd7so1ugpyyj87hghsck2ts.png)
Step-by-step explanation:
Given that,
Radius of the neutron stare, R = 20 km = 20,000 m
Time taken by the Neutron star to rotate, t = 1 s
We need to find the speed of a particle on the star's equator. The total distance covered divided by total time taken is called speed of an object. Here,
![v=(2\pi R)/(t)](https://img.qammunity.org/2021/formulas/physics/high-school/rgkfykeml58ek8xbuiwm52m2lyypn9f7yd.png)
![v=(2\pi * 20000)/(1)](https://img.qammunity.org/2021/formulas/physics/high-school/bodt8qdb88m5wwx68udsdhaecex7anqz5d.png)
v = 125663.70 m/s
or
![v=1.25* 10^5\ m/s](https://img.qammunity.org/2021/formulas/physics/high-school/geiwg55vhbxzd7so1ugpyyj87hghsck2ts.png)
So, the speed of a particle on the star's equator is
. Hence, this is the required solution.