Conceptual doubt on frames of reference

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physicsissohard
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Homework Statement
Take unequal masses and tie both of them with a massless inextensible thread. put that on an ideal pulley. now take this system and put it in a spaceship that has zero gravity. now pull the pulley upwards with an acceleration of g. Now the question is will the heavier mass move with respect to the ground(I mean like spaceship ground or whatever)? If not why not? Now another thing is if you observe this with the frame of reference of the heavier mass. there is a pseudo force acting on the mass. and now with newtons 2nd mg-T=ma. (T is tension and a is acceleration). Now tell me what does 'a' here mean, is that acceleration with respect to the ground, with respect to the pulley, or whatever. Now why is it with respect to whatever that answer is? Can you explain how to interpret newtons second law in this case, and what does it mean to apply it here?
Relevant Equations
mg-T=ma.
I can't solve it. this isn't a homework question just a conceptual one. doubt. one more thing is that in a sense I think gravity can be viewed as a pseudo-force, even though it clearly isn't because if it was people on the other side of the earth will be falling off lol. but for the pulley question accelerating the pulley upwards with g has the same effect Force of gravity.
 
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physicsissohard said:
will the heavier mass move with respect to the ground(I mean like spaceship ground or whatever)?
Yes.
physicsissohard said:
if you observe this with the frame of reference of the heavier mass. there is a pseudo force acting on the mass. and now with newtons 2nd mg-T=ma. (T is tension and a is acceleration). Now tell me what does 'a' here mean,
In the reference frame of the mass, it does not accelerate. The pseudoforce is equal and opposite to the tension.
##ma_{observed}=T+ma_{pseudo}=0##.
 

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