Calculating Force of Link 2 on Link 1 in Chain of 5 Links

[emilinus]

umm this question seems simple enough but I don't really know what I'm doing...

A chain consisting of 5 links, each of mass .100 kg is lifted vertically upwards with a constant acceleration of 2.50 m/s^2. Calculate the force that link 2 exerts on link 1.

so what I did was add the masses of links 2-5 (m=0.4 kg) and multiply this by the acceleration.

so my answer is F21 = 1 N
I have no idea if this is even close to what I'm supposed to do.
Help would be appreciated, thanks.

 

[Astronuc]

Assuming the arrangement from top to bottom is 1-2-3-4-5, and the force accelerating them upward is tied to link 1, then link 1 is pulling on the combined mass of links 2, 3, 4 and 5. So there is the weight due to gravity and the force imposed by the acceleration of 2.5 m/s².