Q.

A body of mass 200 g is tied to a spring of spring constant 12.5 N/m, while the other end of spring is fixed at point O. If the body moves about O in a circular path on a smooth horizontal surface with constant angular speed 5 rad/s, then the ratio of extension in the spring to its natural length will be             [2023]

1 1 : 1  
2 2 : 3  
3 2 : 5  
4 1 : 2  

Ans.

(2)

Natural length=L0

Extension=x

kx=m(L0+x)ω2

12.5x=15(L0+x)251.5x=L0

xL0=23