Calculating Speed and Distance for a Body on a Stretched Spring

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i added a picture of the problem!

when the body is at point A the spring
is in relaxed status.
it lengths in relaxed statues is 0.6m

then a power P =20N is pulling the body to point B AB=0.25m
i was asked what is his speed when it reaches point B

so i made an equation that the total work equals the energy in the end
minus 0 (because there were no energy at the start)
i got that the speed of the body is square root of 15
v=3.87m/sec

the power P stops working a point B permemantly.
now i am being asked

what is the minimal distance that that body will get to the wall?

i tried to do the equation the bodies kinetic enrgy equals to its spring potential energy
it doesn't work i get that the amplitude is longer than 0.6m (not possible)
please help
 

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transgalactic said:
so i made an equation that the total work equals the energy in the end
minus 0 (because there were no energy at the start)
i got that the speed of the body is square root of 15
v=3.87m/sec

My calculation agrees.

the power P stops working a point B permemantly.
now i am being asked

what is the minimal distance that that body will get to the wall?

i tried to do the equation the bodies kinetic enrgy equals to its spring potential energy
it doesn't work i get that the amplitude is longer than 0.6m (not possible)
please help

Can we see your steps please?
 
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