Q.

Two blocks with masses 100 g and 200 g are attached to the ends of springs A and B as shown in the figure. The energy stored in A is E. The energy stored in B, when spring constants kA and kB of A and B, respectively satisfy the relation 4kA=3kB is:             [2026]

1 2E  
2 4E  
3 43E  
4 3E  

Ans.

(4)

For equilibrium kx=mg

U=12kx2=12m2g2k

Um2k

UAUB=(mAmB)2(kBkA)=(12)2(43)=13

EUB=13  UB=3E