# Calculate Maximum Spring Compression: 0.4 kg Object, 80 N/m Constant

• cooney88

#### cooney88

Q. An object of mass o.4kg slides at 8m/s across a frictionless path before striking one end of a spring that is fixed at the other end. the spring constant is 80N/m. the maximum distance, in metres, by which the spring compressed is : ans?

I a not sure wether to use hookes law (f=ks) or the kinetic energy formula Ek = .5kmv^2

when i used hookes law i got an answer of 0.04 but when i use the kinetic energy forumla i got 0.57. I know it doesn't really make any sense to use hookes law as u can't find the force, only the momentum (0.4x 8)

any help with this would be greatly apreciated

## The Attempt at a Solution

It sounds like you're answering your own question. so its the kinetic formula cos it wouldn't make sense to use the hookes law right? but since when can u have the spring constant in a kinetic energy formula?

so its the kinetic formula cos it wouldn't make sense to use the hookes law right?
Yes, you'll need to use energy conservation.
but since when can u have the spring constant in a kinetic energy formula?
Consider the potential energy stored in a compressed spring--that's where the spring constant appears.

cheers buddy