Mechanics falling motion Q (1 Viewer)

[gahyunkk]

How do i do this one?
I found the equations for v in terms of t and x but when i try to combine it to get the answer, it's not working.

 

[dunjaaa]

Took me a while to figure this out; so find the equation of the displacement of both particles.
You should get x(1)=-(1/k)[gt+(1/k)(g+ku)(e^(-kt)-1)] and x(2)=(1/k)[gt+(1/k)(g-ku)(e^(-kt)-1)].
These two particles will intersect when x(1)+x(2)=d. Make t the subject and it comes out

 

[gahyunkk]

Thanks! I got it