Question

A block of initial mass m moving with speed v compreses a spring through distance x before its speed halved value of spring constant

Answer 1

let the mass be m

and velocity =v

spring costant is =k

distance be x

as speed is halved ...

so v = v'/2

so according to conservation of energy ,

1/8mv'² = 1/2kx²

1/4 mv'² =kx²

k = 1/4mv'²x²

hope its help you ...