Q.

Two simple pendulums having lengths l1 and l2 with negligible string mass undergo angular displacements θ1 and θ2, from their mean positions, respectively. If the angular accelerations of both pendulums are same, then which expression is correct          [2025]

1 θ1l22=θ2l12  
2 θ1l1=θ2l2  
3 θ1l12=θ2l22  
4 θ1l2=θ2l1  

Ans.

(4)

Angular frequency of simple pendulum, ω=gl

Angular acceleration, α=ω2θ

 gl1θ1=gl2θ2

 θ1l2=θ2l1