The block moving at instant the spring is compressed 15cm is √[(25m - 45)/m]
When there is no external force acting on the system, the total mechanical energy remains conserved.
K.E i = K.E f + SPE
1/2 mu² =1/2 mv² + 1/2 kx²
Substitute u = 5m/s, k =2000N.m and x =0.15m, we get the final velocity
1/2 mu² =1/2 mv² + 1/2 kx²
v =√[(25m - 45)/m]
Thus, the block moving at the instant the spring has been compressed 15 cm is √[(25m - 45)/m]
Learn more about conservation of energy principle.
https://brainly.com/question/13097206
#SPJ1