Solve Rotational Motion Homework: Pulleys A, B, C

[freshbox]

Homework Statement

Attached 1st pic is the question, 2nd pic is the formula

PS: I am sorry if i have posted on the wrong section.

The Attempt at a Solution

My understanding for this question is for compound pulley, angular velocity is the same, linear velocity is different. For pulleys in contact, linear velocity is the same and angular velocity is different.

Since in this case, A/B are compound pulleys whereas B/C are contact pulleys.
But the question did not give me any acceleration info on any of the pulleys, so I don't know where to start..

The only info that I can gather is:

ωi=0m/s²
s=17m
t=20s

So I tried to use s=rδ formula.
17=0.15δ
δ=113.33

Although I managed to get "1" of the answer, but the info I used was all from pulley A but the answer they want is gears B/C so I'm abit confused here.
Hope someone can help me out.Thanks.

 

[tiny-tim]

welcome to pf!

hi freshbox! welcome to pf!

… the question did not give me any acceleration info on any of the pulleys, so I don't know where to start..

start by finding the (linear) acceleration of the weight D

 

[freshbox]

Hi tiny-tim thanks for the tip, i solved the problem already :)