Question

Certain neutron stars are believed to be rotating at about 1 rec/sec. If such a star has a radius of 20 km, the acceleration of an object on the equator of the star will be

• A. $20\times {10}^{8}m/se{c}^2$
• B. $8\times {10}^{5}m/se{c}^2$
• C. $120\times {10}^{5}m/se{c}^2$
• D. $4\times {10}^{8}m/se{c}^2$

Answer 1

The correct option is B $8\times {10}^{5}m/se{c}^2$

$a={\omega }^{2}r=4{\pi }^2{n}^{2}r=4{\pi }^2\times 1^2\times 20\times {10}^3$
$\therefore a=8\times {10}^{5}m/se{c}^2$