A spring with a constant of #2/5 (kg)/s^2# is lying on the ground with one end attached to a wall. An object with a mass of #7/5 kg# and speed of #2 m/s# collides with and compresses the spring until it stops moving. How much will the spring compress?

1 Answer
Mar 31, 2017

Answer:

I got #3.7m#

Explanation:

At the start there will be the Kinetic Energy #K# of the object that will be converted into Elastic Potential Energy #U_(el)# by compressing the spring.
So we have:
#K=U_(el)#
or:
#cancel(1/2)mv^2=cancel(1/2)kx^2#
the compression #x# will then be given by:
#x=vsqrt(m/k)=2sqrt((7/5)/(2/5))=2sqrt(7/2)=3.7m#