Question

a block of mass 'm' moving with a speed v compresses a spring through

Answer 1

hey friend your answer is 3mv^2/4x^2

Answer 2

reduced velocity = v-(25/100)v=v-(1/4)v=3v/4

1/2 mv2 = 1/2 kx2

➡mv2=kx2

➡m(3v/4)^2=kx^2

➡m(9v^2/16)=kx^2

➡k=9mv^2/16x^2=3mv^2/4x^2