Question

In each of the cases shown in the figure, the block has been displaced by the same amount from equilibrium. Rank the cases based on the elastic potential energy stored in the springs.

Answer 1

case4 > case 2 > case 5 > case 3 >case 1

Step-by-step explanation:

if displacement is same for all, then potential energy PE depends on k

case 1)

K1 = k * 2k / (k+2k) =2k/3 (due to series combination of them)

case 2)

K2 =k+k =2k 9 (due to parallel combination of them)

case 3)

K3 =k (single body)

case 4)

K4 =(k*k/2k)+ 2k =k/2 +2k = 5k/2

(due to both series combination of the first two and parallel combination of the last)

case 5)

K5 =(k+2k)*3k/(k+2k+3k) = 3k/2

(due to the parallel combination of k and 2k and then a series combination with 3k)

Hence, the order of PE from greatest to lowest

case4 > case 2 > case 5 > case 3 >case 1