Isaac Physics question

https://isaacphysics.org/questions/metal_block

I am not sure how to do part b of this question, I have done part a and c but I am very stuck on part b.

for the part where it is accelerating, I know that V=a_n*t and s1 = 0.5*a*t^2

after the string snaps 1/2mv^2 = F_r * s2

so i thought that(mv^2)/2F_r + (0.5 * a* t^2) would be the total displacement but this is wrong, I am not sure how to work this out any other way.

Part b) is about tension & acceleration ratios, not string breaking and displacements?

Oh Yh sorry I meant part c I forgot about part A ( I’ve done a,b and d then )

The net force acting on the body is a positive constant (difference between tension and resistance) before the string breaks. Then a negative constant (-resistance) after it breaks. Just model that in terms of two distance suvats and the velocity suvat until the string breaks. Post what you try.

Not really sure about some of the bits in your work but it looks verbose. For the first part:
s = a_n * t^2 / 2
v = a_n * t
So for the second part
s = (a_n * t)^2 / (2F_r/m)
add the 2 displacements. That should be about it (may have got the odd bit of notation wrong).

Thank you, this is what I originally thought as well but for some reason it’s not right, I’ve tried lots of different things but none of them are working.

I get it correct. Upload a pic of what you actually entered?