Slide Block Problem With Strings

[Hypnos_16]

Three blocks on a frictionless surface are connected by massless strings, with M1 = 1.30kg, M2 = 2.20kg, and M3 = 3.40kg. Due to the force F acting on M3, the system accelerates to the right. Given that T1 is 4.10Newtons, calculate T2.

M1 = 1.30 kg
M2 = 2.20 kg
M3 = 3.40 kg
and T1 = 4.10N

it looks like this

(M1)---T1---(M2)---(T2)---(M3)------> F

i don't know what to do here, i don't know if the whole thing moves as one, or if the force is just on M3 and all the other ones would have different forces working on them.
I'm very confused

 

[tiny-tim]

Hi Hypnos_16!

Three blocks on a frictionless surface are connected by massless strings, with M1 = 1.30kg, M2 = 2.20kg, and M3 = 3.40kg. Due to the force F acting on M3, the system accelerates to the right. Given that T1 is 4.10Newtons, calculate T2.
…
(M1)---T1---(M2)---(T2)---(M3)------> F

i don't know what to do here, i don't know if the whole thing moves as one, or if the force is just on M3 and all the other ones would have different forces working on them.

It does both!

Yes, the whole thing moves as one …

first treat the whole thing as a single body with only one external force (F): that gives you the acceleration​

but you can also look at the forces just on M₃ (or any other mass) …

then pick off the masses one at a time (I'd start from the left), using the acceleration you've already found, to find the individual tensions ​