Question

when 2 bodies are rigidly connected to a string, say, m1 and m2, do they have the same acceleration or different? don't consider the direction of the acceleration, just the magnitude. PLEASE BE SURE AND ANSWER. thank you :)

Answer 1

     If the string is rigid , tight, inextensible with tension > 0, then the two bodies have the same (magnitude of)  acceleration, along the direction of the string on either side. 

If the string is loose or folded, then the accelerations cannot be inter-related easily.

I suppose there is no rotation of the two bodies..

Is this question / doubt from the  topic  pulleys, bodies attached to strings rolling over pulleys?    Then yes, certainly.